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                                                                     Exhibit 2.7

                                                                       EXECUTION

                           THIRD AMENDED AND RESTATED
                            SECURITYHOLDERS AGREEMENT

                                  by and among

                     MAXCOM TELECOMUNICACIONES, S.A. DE C.V.
                   (formerly known as Amaritel, S.A. de C.V.)

                                       and

                         CERTAIN OF ITS SECURITYHOLDERS

                            DATED AS OF JULY 20, 2006

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                                TABLE OF CONTENTS

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<S>                                                                         <C>
SECTION 1. DEFINITIONS...................................................      2

SECTION 2. BOARD OF DIRECTORS............................................      8
   (A) BOARD COMPOSITION.................................................      8
   (B) DIRECTOR VACANCIES................................................      9
   (C) SUBSIDIARY BOARDS.................................................      9
   (D) COMMITTEES........................................................      9
   (E) ADVISORY COMMITTEE................................................      9
   (F) REMOVAL OF DIRECTORS..............................................      9
   (G) COVERED PERSONS LIABILITY.........................................     10
   (H) EXPENSES..........................................................     10

SECTION 3. BOARD AND SECURITYHOLDER ACTIONS..............................     10
   (A) REQUIRED APPROVALS................................................     10
   (B) NEXUS KEY MATTERS.................................................     11
   (C) GRUPO VAC KEY MATTERS.............................................     12
   (D) NEXUS AND GRUPO VAC KEY MATTERS...................................     12
   (E) GRUPO VAC VOTING LIMITATIONS......................................     14
   (F) ADDITIONAL APPROVALS..............................................     14
   (G) GRUPO VAC VOTING RIGHTS TERMINATION...............................     14

SECTION 4. COVENANTS.....................................................     15
   (A) FINANCIAL STATEMENTS AND OTHER INFORMATION........................     15
   (B) COMPLIANCE WITH U.S. FOREIGN CORRUPT PRACTICES ACT................     17
   (C) INSPECTION OF PROPERTY............................................     17
   (D) CONFIDENTIALITY...................................................     17
   (E) UBTI..............................................................     18
   (F) SHAREHOLDERS MEETINGS.............................................     18

SECTION 5. RESTRICTIONS ON TRANSFER OF SHARES............................     18
   (A) TRANSFER OF SHARES................................................     18
   (B) RESTRICTED SHARES.................................................     18
   (C) RIGHTS OF FIRST REFUSAL ON TRANSFERS BY NON-INVESTORS.............     19
   (D) RIGHT OF FIRST OFFER ON TRANSFERS BY INVESTORS (OTHER THAN BA
          INVESTORS).....................................................     20
   (E) PARTICIPATION (TAG-ALONG) RIGHTS IN TRANSFERS.....................     21
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<S>                                                                         <C>
   (F) DRAG ALONG RIGHTS.................................................     23
   (G) GRUPO VAC RIGHT OF FIRST OFFER ON CERTAIN TRANSFERS AND LIMITED
          OFFER RIGHT ON CERTAIN SALE OF COMPANY TRANSACTIONS............     25
   (H) AGREEMENT REGARDING INDIRECT TRANSFERS............................     30
   (I) PERMITTED TRANSFEREES.............................................     31
   (J) PUBLIC OFFERING PROVISIONS........................................     31
   (K) SHARES HELD BY CPO TRUSTEE........................................     34
   (L) PARTICIPATION RIGHT (TAG-ALONG RIGHTS) ON TRANSFERS BY QUALIFIED
          INVESTORS TO OTHER QUALIFIED INVESTORS.........................     34
   (M) RESTRICTION ON COMPETITION BY GRUPO VAC INVESTORS.................     36
   (N) TERMINATION.......................................................     36

SECTION 6. FOREIGN INVESTMENT AND TELECOMMUNICATION LAW..................     37

SECTION 7. SHARE CERTIFICATE NOTATION....................................     37

SECTION 8. MISCELLANEOUS.................................................     38
   (A) AMENDMENT AND WAIVER..............................................     38
   (B) SUCCESSORS AND ASSIGNS............................................     38
   (C) COUNTERPARTS......................................................     38
   (D) NOTICES...........................................................     38
   (E) GOVERNING LAW; JURISDICTION.......................................     39
   (F) ARBITRATION.......................................................     39
   (G) GOVERNING LANGUAGE................................................     40
   (H) U.S. GAAP.........................................................     40
   (I) RULE OF CONSTRUCTION..............................................     40
   (J) FURTHER ASSURANCES................................................     40
   (K) COMPLETE AGREEMENT................................................     40
   (L) SPECIAL PROVISIONS FOR OPTIONHOLDERS..............................     40
   (M) TERMINATION OF AGREEMENT..........................................     41
   (N) UNDERSTANDING AMONG THE SECURITYHOLDERS...........................     41
   (O) ACKNOWLEDGMENT RE KIRKLAND & ELLIS LLP............................     42
</TABLE>
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                           THIRD AMENDED AND RESTATED
                            SECURITYHOLDERS AGREEMENT

          THIS THIRD AMENDED AND RESTATED SECURITYHOLDERS AGREEMENT (this
"Agreement") is entered into as of July 20, 2006 by and among (i) Maxcom
Telecomunicaciones, S.A. de C.V. (formerly known as Amaritel, S.A. de C.V.), a
corporation organized under the laws of Mexico (the "Company"), (ii) each of the
entities listed on the signature pages hereto, and (iii) each of the
shareholders of the Company listed on the signature pages hereto. The
shareholders and, as applicable, optionholders are referred to herein
collectively as the "Securityholders" and individually as a "Securityholder".
Except as otherwise indicated herein, capitalized terms used herein are defined
in Section 1 hereof.

          WHEREAS, on May 21, 1998, the Company, certain investors, the Existing
Securityholders and Bancomer, S.A., Institucion de Banca Multiple, Grupo
Financiero Bancomer, Direccion Fiduciaria, as trustee, executed and delivered an
Irrevocable Administration and Security Trust Agreement (as amended from time to
time, the "Security Trust Agreement");

          WHEREAS, on May 23, 1998 the Company shareholders entered into a
Securityholders Agreement (the "Original Securityholders Agreement");

          WHEREAS, on February 21, 2000, the Company shareholders approved a
restructuring of the Company's capital structure, including the authorization of
(i) the issuance of nominative Series C shares of the Company with full voting
rights and no par value (the "Series C Shares"), (ii) the conversion of a
portion of the then existing Series A, Series B and Series N Shares into Series
C Shares, (iii) creation of an Irrevocable Neutral Investment Trust (the
"Neutral Investment Trust"), into which the Company (with respect to certain
treasury stock) and the holders of Series N Shares and certain holders of Series
A Shares and Series B Shares deposited such shares, fifty percent of which
shares, simultaneously with their deposit into the trust estate, were converted
into Series C Shares (and in the case of the Series A Shares and Series B
Shares, were converted into Series C Shares and Series N Shares), and (iv) the
issuance by Banco Nacional de Mexico, S.A., Institucion de Banca Multiple, Grupo
Financiero Banamex Accival, Division Fiduciaria as Trustee with respect to the
Neutral Investment Trust of ordinary participation certificates to the settlors
of the Neutral Investment Trust (with each one ordinary participation
certificate representing one Series C Share and one Series N Share)
(collectively, the "First Restructuring");

          WHEREAS, on August 18, 2000 the Original Securityholders Agreement was
amended and restated to, among other things, reflect the First Restructuring (as
amended and restated, the "First Amended and Restated Securityholders
Agreement");

          WHEREAS, on March 5, 2002, the Company shareholders approved, a second
restructuring of the Company's capital structure, including the authorization of
(i) the conversion of the issued and outstanding Series C Shares into Series N
Shares, (ii) the termination and liquidation of the Neutral Investment Trust,
(iii) the elimination of certain ownership restrictions on the Series N Shares,
(iv) the elimination of the voting rights of Series N Shares, (v) the increase
in the authorized capital stock of the Company, (vi) the authorization and
issuance of preferred Series A-1 Shares, Series B-1 Shares, Series N-1 Shares
and Series N-2 Shares and (vii) the granting of certain approval rights to the
Series B-1 Shares (collectively, the "Second Restructuring");


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          WHEREAS, the General Bureau of Foreign Investment of the Ministry of
Economy of Mexico (the "Bureau") reviewed and approved the Second Restructuring
and the issuance of the new shares created thereunder;

          WHEREAS, on April 22, 2002, the Company filed its Second Amended and
Restated Bylaws with the Public Registry of Property and Commerce of Mexico,
Federal District and with the Bureau for approval of all provisions of such
Second Amended and Restated Bylaws which differed from the form of the Company
Bylaws submitted previously to the Bureau for approval, and the Bureau approved
all such provisions;

          WHEREAS, as of April 29, 2002, the Neutral Investment Trust was
terminated and the shares of the Company deposited therein were distributed to
the holders;

          WHEREAS, on April 29, 2002 the parties hereto amended and restated the
First Amended and Restated Securityholders Agreement for purposes, among other
things of: (i) including new shareholders of the Company as parties, (ii)
reflecting the Second Restructuring, (iii) amending the rights of the existing
Series A Shares, Series B Shares and Series N Shares, (iv) establishing the
rights of new Series A-1 Shares, Series B-1 Shares, Series N-1 Shares and Series
N-2 Shares and (v) amending the composition and operation of the Company's Board
of Directors (the "Board");

          WHEREAS, on July 17, 2006 the Company shareholders approved a
restructuring of the Company's capital structure, including the authorization of
(i) the issuance of 2,825,124 Series A Shares and 75,988,379 Series N Shares
(the "Grupo VAC Shares") representing approximately 16.34% of the total Shares
of the Company authorized as of the signing date and (ii) the conversion of all
then existing Series A-1, Series B-1, Series N-1 and Series N-2 Shares into
Series A, Series B and Series N Shares, respectively, along with the elimination
of certain preferred rights (collectively, the "Third Restructuring");

          WHEREAS, the Company will file on or prior to July 31, 2006 its Third
Amended and Restated Bylaws, a true and complete copy of the English translation
of which is attached hereto as Exhibit A with the Public Registry of Property
and Commerce of Mexico, Federal District; and

          WHEREAS, the parties hereto desire to amend and restate the Second
Amended and Restated Securityholders Agreement for purposes, among other things
of: (i) including new shareholders of the Company as parties, (ii) reflecting
the Third Restructuring, (iii) amending the rights of the existing Series A
Shares, Series B Shares and Series N Shares, (iv) eliminating the rights of
Series A-1 Shares, Series B-1 Shares, Series N-1 Shares and Series N-2 Shares,
and (v) amending the composition and operation of the Company's Board of
Directors (the "Board").

          NOW, THEREFORE, in consideration of the mutual covenants contained
herein and other good and valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, the parties hereto hereby amend and restate the
Second Amended and Restated Securityholders Agreement to reflect (i) the
inclusion of the Grupo VAC Investors as a party hereto, (ii) the omission of
certain former Shareholders as parties hereto and (iii) the following
agreements:

     SECTION 1. Definitions.


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     Capitalized terms used herein will have the meaning set forth in this
Section 1.

     "Advisory Committee" has the meaning set forth in Section 2(e).

     "Affiliate" of any Person means any other Person controlling, controlled by
or under common control with such particular Person, and "control" means the
possession, directly or indirectly, of the power to direct the management,
policies, assets and ownerships of a Person, whether through the ownership of
voting securities, contract or otherwise.

     "Aguirre Group Investors" means, with respect to the Series A Shares only,
collectively, Adrian Aguirre G., Maria Guadalupe Aguirre G. and Maria Elena
Aguirre G., and their respective successors in interest and Permitted
Transferees.

     "Approved Plan" has the meaning set forth in Section 3(d)(iv).

     "BA Investors" means, collectively, BankAmerica International Investment
Corporation, BankAmerica Investment Corporation, BASCFC-Maxcom Holdings I, LLC,
BAS Capital Funding Corporation, Nexus-Maxcom Holdings I, LLC, Nexus-Banc of
America Fund II, L.P., Edward McCaffrey and their respective successors in
interest and Permitted Transferees.

     "Bachow Investors" means, collectively, Bachow Investment Partners III, LP
("BIP"), Bachow & Associates, Inc., each of the limited partners of BIP, the
general partner of BIP (and its limited partners and general partners), the
direct and indirect equity holders of any thereof, Paul S. Bachow, Salvatore A.
Grasso and Jay D. Seid and each of their respective successors and permitted
assigns and permitted transferees.

     "Bank of America" means, Bank of America Corporation and any successor in
interest thereto.

     "Bansi Credit Agreement" means the credit agreement with fiduciary
guarantee and joint guarantor, dated as of December 20, 2004, by and between
Bansi, S.A. Institucion de Banca Multiple as Lender, Telereunion, S.A. de C.V.
as Borrower and Telereunion International, S.A. de C.V. as Guarantor for an
amount of up to MX$51,000,000.00.

     "Bureau" has the meaning set forth in the recitals to this Agreement.

     "Board" has the meaning set forth in the recitals to this Agreement.

     "Business" means the business of providing local, long distance and network
telecommunications services in Mexico pursuant to concessions and/or permits
issued by the Mexican government and the sale or rental of related equipment to
subscribers of such services.

     "Committee" has the meaning set forth in Section 2(d).

     "Company" means Maxcom Telecomunicaciones, S.A. de C.V., a Mexican stock
corporation with variable capital, and any successor-in-interest thereto.

     "Company Bylaws" means that certain Maxcom Telecomunicaciones, S.A. de C.V.
Third Amended and Restated By-Laws, dated as of July 17, 2006, as such agreement
may be amended


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from time to time thereafter pursuant to the terms and restrictions set forth
therein, a true and complete copy of which is attached as Exhibit A hereto.

     "Covered Persons" has the meaning set forth in Section 2(g).

     "Covered Transaction" has the meaning set forth in Section 5(g)(v).

     "CPO" means a certificate of participation issued to a beneficiary of the
trust established pursuant to the CPO Investment Trust Agreement.

     "CPO Investment Trust Agreement" means that certain Irrevocable Investment
Trust Agreement, dated as of April 29, 2002, by and among the Company and the
bank initially appointed by Company as the trustee thereunder, as such agreement
may be amended from time to time thereafter pursuant to its terms and the
restrictions set forth in the Company Bylaws.

     "CPO Trustee" means the trustee under the CPO Investment Trust Agreement
and any successor thereto.

     "Drag-Along Sale" has the meaning set forth in Section 5(f)(i).

     "Equity Securities" means any equity securities of an issuer or debt
securities of an issuer with equity features or other securities exercisable or
convertible into equity securities of such issuer or any of its subsidiaries
(including, without limitation, Options) or any other securities of such issuer
containing any profit participation features (including, without limitation,
stock appreciation rights and phantom stock).

     "Exempt Transfers" has the meaning set forth in Section 5(b).

     "Family Group" with respect to a natural person, means such natural
person's spouse, parents, siblings and descendents (whether natural or adopted)
and any trust solely for the benefit of such natural person and/or such natural
person's spouse and/or descendents (whether natural or adopted).

     "Grupo VAC Agreements" means the TR Purchase Agreement, the Holdback Trust
Agreement, CFE Credit Agreement, Security Trust Agreement, Securityholders'
Agreement, the Post-Closing Matters Side Letter Agreements, the Bansi Credit
Agreement, and any agreement between the Company or any of its Subsidiaries and
Sierra Communications Globales, S.A. de C.V.

     "Grupo VAC Director" has the meaning set forth in Section 2(a)(i).

     "Grupo VAC Investors" means Eduardo Vazquez Arroyo Carstens, Gabriel
Agustin Vazquez Arroyo Carstens, Alina Georgina Carstens de Vazquez Arroyo,
Telereunion International, S.A. de C.V., Controladora Profesional Regiomontana,
S.A. de C.V., and their respective successors in interest and Permitted
Transferees.

     "Grupo VAC Key Matter" has the meaning set forth in Section 3(c).

     "Grupo VAC Limited Offer" has the meaning set forth in Section 5(g).


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     "Grupo VAC Offer" has the meaning set forth in Section 5(g)(ii).

     "Grupo VAC Offer Right Conditions: has the meaning set forth in Section
5(g)(i).

     "Grupo VAC RLO Notice" has the meaning set forth in Section 5(g).

     "Grupo VAC Representative" means Eduardo Vazquez Arroyo Carstens so long as
he is a Grupo VAC Investor, and thereafter, such person as designated in writing
to the Company by the Grupo VAC Investors holding a plurality of all Shares held
of record by the Grupo VAC Investors.

     "Grupo VAC ROFO Notice" has the meaning set forth in Section 5(g)(i).

     "Grupo VAC Threshold Percentage" means 11%; provided, however, that if,
after the date the Company Bylaws are adopted by the shareholders, the Company
issues Shares as consideration for the acquisition by the Company or its
subsidiaries of the assets or capital stock of one or more companies, and as the
result of such issuance of Shares, the Grupo VAC Investors' beneficial ownership
of outstanding Shares is less than 11%, then the Grupo VAC Threshold Percentage
shall be 7%.

     "Guidelines" means the Company Guidelines attached hereto as Exhibit B.

     "Holdback Trust Agreement" means the Irrevocable Administration and
Holdback Security Trust Agreement, dated as of July 20, 2006, as such agreement
may be amended from time to time thereafter pursuant to its terms, among the
Company, the Grupo VAC Investors and Banco Mercantil del Norte, S.A.,
Institucion de Banca Multiple, Grupo Financiero Banorte, as trustee.

     "Independent Third Party" means, at any applicable date of determination,
any Person, other than any holder of more than 5% of the Shares issued and
outstanding on such date; provided, however, that the Grupo VAC Investors and
their Affiliates shall be deemed Independent Third Parties hereunder for
purposes of the definition of "Sale of the Company".

     "Investors" means the Aguirre Group Investors, BA Investors, the Grupo VAC
Investors, the Bachow Investors, Latinvest Strategic Investment Fund, L.P., and
Credit Suisse First Boston Corporation. For purposes of the registration rights
set forth in Section 5(j), "Investor" also includes L.D. Coltrane, III, Michael
R. Coltrane, Samuel E. Leftwich and Thomas A. Norman.

     "Investor Transfer Notice" has the meaning set forth in Section 5(d)(i).

     "Neutral Investment Trust" has the meaning set forth in the recitals to
this Agreement.

     "Nexus" means, collectively, Nexus-Maxcom Holdings I, LLC and Nexus-Banc of
America Fund II, L.P. (together with any successor-in-interest).

     "Nexus Director" has the meaning set forth in Section 2(a)(ii).

     "Nexus Key Matter" has the meaning set forth in Section 3(b).

     "Non-CPO Securityholder" has the meaning set forth in Section 5(c)(i).


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     "Offer Notice" means a notice disclosing the number of Shares to be
transferred, the proposed price, terms and conditions of the Transfer and the
identity of the prospective transferee(s) who submitted the offer.

     "Option" means a right, option or warrant to subscribe for or to purchase
any series of Shares.

     "Permitted Transferees" has the meaning set forth in Section 5(i).

     "Person" means an individual, a partnership, a corporation, a limited
liability company, an association, a joint stock company, a trust, a joint
venture, an unincorporated organization, or a governmental entity or any
department, agency or political subdivision thereof.

     "Post-Closing Matters Side Letter Agreement" has the meaning set forth in
the TR Purchase Agreement.

     "Public Offering" means the consummation of a public offering (whether a
primary or a secondary offering) registered under the Mexican securities laws,
rules and regulations or the Securities Act of Shares, CPOs, certificates of
participation, American depositary receipts or other similar securities
representing an economic ownership interest in Shares.

     "Public Sale" means any sale of Shares to the public (i) pursuant to an
offering registered under the Mexican securities laws and/or the United States
securities laws in accordance with the registration statement covering such
Shares or (ii) through a broker, dealer or market maker pursuant to the
provisions of Rule 144 (or similar provision then in force) adopted under the
United States securities laws.

     "Qualified Affiliate" of any Person means (i) any other Person 90% or more
of whose equity and other voting securities are beneficially owned by such
Person or (ii) any other Person who beneficially owns 90% or more of the equity
and other voting securities of such Person (it being understood that,
notwithstanding the foregoing, each of the BA Investors, Nexus Partners I, LLC
(and any private equity fund managed by Nexus Partners I, LLC) and any Affiliate
of Bank of America in which Bank of America holds, directly or indirectly, at
least a majority of the economic interests thereof shall be deemed to be
Qualified Affiliates of one another).

     "Qualified Investor" has the meaning set forth in Section 5(d)(i).

     "Qualified Public Offering" means a Public Offering that yields aggregate
net proceeds to the Company of at least U.S.$50,000,000 (fifty million U.S.
dollars).

     "Recusal" has the meaning set forth in Section 5(g)(xi).

     "Registration Request" has the meaning set forth in Section 5(j)(ii).

     "Regulatory Amendments" means any amendment of the Foreign Investment Law
and the Federal Telecommunications Law of Mexico permitting the unrestricted
ownership and/or control of the Company by one or more foreign entities.

     "Required Approvals" has the meaning set forth in Section 3(a).


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     "Restricted Matters" has the meaning set forth in Section 5(g)(xi).

     "Restricted Persons" has the meaning set forth in Section 3(d)(ii).

     "Restricted Share(s)" has the meaning set forth in Section 5(b).

     "Restricted Share Transfer Consent" has the meaning set forth in Section
5(b).

     "RFR Free Transfer Period" has the meaning set forth in Section 5(c)(iii).

     "ROFO Free Transfer Period" has the meaning set forth in Section 5(d)(iii).

     "ROFO-RLO Free Period" has the meaning set forth in Section 5(g)(ii).

     "Sale of the Company" shall mean any transaction or series of related
transactions involving (i) a sale of all or substantially all of the
consolidated assets of the Company to any Independent Third Party or group of
Independent Third Parties or (ii) a merger, recapitalization or reorganization
of the Company, the sale or transfer of assets of, or any equity interest in, or
any securities convertible into or exchangeable for an equity interest, in the
Company, or other similar transaction or business combination involving the
Company, in each case after which at least a majority of the beneficial and
record ownership of the Shares then outstanding would be owned by any
Independent Third Party or group of Independent Third Parties.

     "Second Amended and Restated Bylaws" means the Bylaws of the Company
approved by the shareholders of the Company on March 5, 2002.

     "Securities Act" means the U.S. Securities Act of 1933, as amended, and the
rules and regulations promulgated thereunder.

     "Securityholder" means any shareholder and, as applicable, any optionholder
of the Company.

     "Security Trust Agreement" means the Third Amended and Restated Irrevocable
Administration and Security Trust Agreement, dated as of July 20, 2006, by and
among the Company, certain Securityholders and Bancomer, S.A., Institucion de
Banca Multiple, Grupo Financiero Bancomer, Direccion Fiduciaria, as trustee, as
such agreement may be further amended from time to time thereafter pursuant to
its terms.

     "Series A Directors" has the meaning set forth in Section 2(a)(i).

     "Series B Directors" has the meaning set forth in Section 2(a)(ii).

     "Series A Shares" means the Company's nominative, series A shares with full
voting rights, no par value and which may only be held by Mexican individuals or
Mexican entities with a clause in their by-laws prohibiting foreign ownership.

     "Series B Shares" means the Company's nominative, series B shares with full
voting rights, no par value and which may be held by Mexican and foreign
individuals or entities.


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<PAGE>

     "Series N Shares" means the Company's nominative, series N shares without
voting rights and no par value (and, without limitation of the foregoing, for
all purposes hereunder, includes any securities converted into Series N Shares
on or prior to the date of this Agreement).

     "Shares" means, at any given time, collectively, the Company's (i) Series A
Shares, (ii) Series B Shares, (iii) Series N Shares, and (iv) any subsequently
authorized series or class of capital stock of the Company. For purposes of
clarification, CPOs are not Shares.

     "Strategic Combination" has the meaning set forth in Section 5(g)(vi).

     "Subsidiary Board" has the meaning set forth in Section 2(c).

     "Tag-Along Right Notice" has the meaning set forth in Section 5(e)(i).

     "Tag-Along Window" has the meaning set forth in Section 5(e)(ii).

     "TR Purchase Agreement" means the Share Purchase and Sale Agreement, dated
as of July 20, 2006, by and among Telereunion International, S.A. de C.V.,
Controladora Profesional Regiomontana, S.A. de C.V., Eduardo Vazquez Arroyo
Carstens, Gabriel Agustin Vazquez Arroyo Carstens, the Company and Maxcom
Servicios Administrativos, S.A. de C.V, as such agreement may be amended from
time to time thereafter pursuant to its terms.

     "Transaction Agreements" means (i) the Company Bylaws, (ii) this Agreement,
(iii) the Guidelines attached hereto as Exhibit B, (iv) the Security Trust
Agreement, (v) the CPO Investment Trust Agreement, (vi) any Grupo VAC Agreement,
and (vii) each of the other instruments and agreements contemplated hereby and
thereby. Transaction Agreements shall include, to the extent applicable, each
Transaction Agreement as such agreement may be amended from time to time in
accordance with its terms and this Agreement.

     "Transfer" means, with respect to any interest, any direct or indirect
sale, exchange, transfer, assignment, pledge or other disposition (whether with
or without consideration and whether voluntarily or involuntarily or by
operation of law) of any such interest (including, without limitation, a
beneficial interest in such interest).

     "Transferring Non-Investor Securityholder(s)" has the meaning set forth in
Section 5(c).

     "Transferring Securityholder" has the meaning set forth in Section 5(e)(i).

     SECTION 2. BOARD OF DIRECTORS.

     (a) Board Composition. Subject to the provisions set forth in Section 6
hereof, the Company shall be managed by the Board and the Board shall be
composed of 9 (nine) members and the same number of alternate members. An
alternate member of the Board may only serve as alternate director for the Board
member for whom such alternate Board member is specifically designated to serve
as an alternate. The following individuals shall be elected to the Board:

          (i) 5 (five) members (and 5 (five) alternates) designated by the
     holders of the Series A Shares. Of such Board members and alternates, 1
     (one) member (and its respective alternate) shall be designated by the
     Grupo VAC Investors; provided, however, that (A) the


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     Grupo VAC Investors continue to hold, in the aggregate, at least the Grupo
     VAC Threshold Percentage of the issued and outstanding Shares of Maxcom and
     (B) the Grupo VAC Investors and their respective Affiliates fully comply
     with the conditions set forth in Section 5(m) (the "Grupo VAC Director").
     The remainder of such board members (and alternates) shall be designated by
     the holders of a majority of the Series A Shares present at a shareholders'
     meeting and entitled to vote thereat voting together as a single class on
     any such designation (the "Series A Directors"); and

          (ii) 4 (four) members (and 4 (four) alternates) designated by the
     holders of a majority of the Series B Shares present at a shareholders'
     meeting and entitled to vote thereat voting together as a single class on
     any such designation (the "Series B Directors"); provided, however, that a
     Series B Director (and alternate) shall only be elected if nominated as a
     Series B Director (or alternate, as the case may be), by Nexus (any Series
     B Director actually nominated by Nexus and elected by the holders of a
     majority of the Series B Shares acting jointly, a "Nexus Director");

     (b) Director Vacancies. Unless otherwise required by applicable Mexican
law, if any party entitled to designate a Director pursuant to the terms of this
Section 2 fails to do so, such Director seat shall remain vacant until filled in
accordance with this Section 2.

     (c) Subsidiary Boards. At the request of any Nexus Director or the Grupo
VAC Director, the composition of the board of directors or similar body of each
of the Company's subsidiaries (a "Subsidiary Board") shall include at least 1
(one) Nexus Director and 1 (one) Grupo VAC Director.

     (d) Committees. At the request of any Nexus Director or Grupo VAC Director,
each committee of the Board and each committee of each Subsidiary Board (each, a
"Committee") shall include at least 1 (one) Nexus Director and 1 (one) Grupo VAC
Director.

     (e) Advisory Committee. The Board shall establish an advisory committee
(the "Advisory Committee"). The Advisory Committee shall be responsible for
advising the Board regarding, and shall oversee, the Company's continuing
operations; provided, however, that the Advisory Committee shall not have the
authority to approve any matters and shall only have the authority to recommend
matters to the full Board. The Advisory Committee shall include (i) the
Company's then current Chief Executive Officer, (ii) Adrian Aguirre G., (iii) 1
(one) Grupo VAC Director (so long as the Grupo VAC Investors are entitled to
appoint 1 (one) Grupo VAC Director), and (iv) 3 (three) Series B Directors
(including at least 2 (two) Nexus Directors).

     (f) Removal of Directors. The removal (with or without cause) of any member
of the Board, a Subsidiary Board or a Committee shall be only upon written
request of the Securityholder(s) who designated such member. If any individual
ceases, for any reason, to serve as a member of the Board, a Subsidiary Board or
a Committee, the vacancy shall be filled by a new member selected by the
Securityholder(s) who designated such member. If any member of the Board (or
with respect to a Subsidiary Board or any Committee, any Nexus Director) cannot
attend any meetings thereof, the alternate member designated by the
Securityholder(s) who designated such member (or by Nexus, with respect to the
Nexus Director) may attend such meetings in lieu of the absent Board member, and
such alternate member shall be given all written notices, materials and
information regarding all meetings of the Board, such Subsidiary Board or
Committee and shall be


                                        9

<PAGE>

entitled to vote at such meeting as a member of the Board, such Subsidiary Board
or Committee (it being understood that any alternate member may nonetheless
attend any meeting of the Board, a Subsidiary Board or a Committee of the Board
as an observer and shall be entitled to receive copies of all materials and
information regarding such meeting, even if the principal Board member is
present, but in no event shall such alternate member vote in such meeting of the
Board if the principal Board member is present at such meeting). If a member of
the Board, a Subsidiary Board or a Committee and such member's alternate member
of the Board, Subsidiary Board or Committee both attend a meeting of the Board,
a Subsidiary Board or Committee, only the member of the Board, Subsidiary Board
or Committee (as opposed to the alternate member) shall be entitled to vote at
such meeting.

     (g) Covered Persons Liability. None of the members of the Board, Subsidiary
Board or of any Committee (including alternate members), and none of the
Company's officers (collectively, "Covered Persons") shall be liable to any
Securityholder or the Company for (i) any action taken or inaction in good faith
with respect to the Company which is not a violation of the material provisions
of this Agreement and which is not grossly negligent or willfully malfeasant,
(ii) any action or inaction in good faith arising from reliance upon the opinion
or advice as to legal matters of legal counsel or as to accounting matters of
accountants selected by any of them with reasonable care, or (iii) any action or
inaction in good faith of any agent, contractor or consultant selected by any of
them with reasonable care. In the event of a Covered Person's bad faith, gross
negligence or willful malfeasance in connection with any action taken or
inaction in good faith with respect to the Company which is not a violation of
the material provisions of this Agreement, such Covered Person shall only be
liable to the extent of such bad faith, gross negligence or willful malfeasance.

     (h) Expenses. The Company shall pay the reasonable, documented
out-of-pocket expenses (including reasonable travel and lodging) incurred by
each member (and each alternate member) of the Board in connection with
attending each meeting of the Board, any Subsidiary Board or any Committee
attended by such member (and alternate) and other expenses reasonably incurred
in connection with the discharge of such members' duties as a member of the
Board, any Subsidiary Board or Committee.

     SECTION 3. BOARD AND SECURITYHOLDER ACTIONS.

     (a) Required Approvals. The approval of each of the Key Matters listed in
this Section 3 ("Required Approvals") shall be submitted to the Board for
authorization and approval; provided, however, that the Board approval shall
also require the affirmative vote of at least 1 (one) Nexus Director with regard
to Nexus Key Matters and, except as set forth in Sections 3(e) and 3(g), 1 (one)
Grupo VAC Director with regard to Grupo VAC Key Matters. In addition, (i) each
Nexus Key Matter shall require the approval of Nexus, solely in its capacity as
a Shareholder (and without any fiduciary duty to the Company or any of the
Shareholders) and (ii) except as set forth in Sections 3(e) and 3(g) below, each
Grupo VAC Matter shall require the approval of the Grupo VAC Representative
acting on behalf of all of the Grupo VAC Investors, solely in his capacity as
the Grupo VAC Representative (and without any fiduciary duty to the Company or
any of the Shareholders, including any Grupo VAC Investor). The Company shall
take (or cause to be taken) all necessary actions so that any Nexus Key Matter
or Grupo VAC Key Matter which is submitted to the Shareholders for approval (in
lieu of approval by the Board) shall also be subject to the approval


                                       10

<PAGE>

of Nexus or the Grupo VAC Representative (on behalf of the Grupo VAC Investors),
as applicable. Any approval rights of Nexus in its capacity as a Shareholder
under this Section 3(a) may also be exercised in writing by Bank of America on
behalf of Nexus.

     (b) Nexus Key Matters. The following subject-matters shall each be
considered a "Nexus Key Matter" requiring special approval thereof as set forth
in Section 3(a):

          (i) the issuance of any Equity Securities of the Company or any of its
     subsidiaries other than 28,368,087 shares (as adjusted for stock splits,
     stock dividends, recapitalizations and similar events) issued pursuant to
     existing stock options and management incentive plans of the Company shown
     on the Company's records (as of the date of the approval of these Bylaws by
     the Company's shareholders) as reserved for future issuance pursuant to
     such stock options and existing management incentive plans;

          (ii) the declaration, setting aside or payment of any dividends on, or
     making any other distributions in respect of, any of its capital stock,
     other than dividends and distributions by a direct or indirect wholly-owned
     subsidiary of the Company to its parent;

          (iii) the purchase, redemption or other acquisition of any Equity
     Securities of the Company or any of its subsidiaries or reduction in
     capital of any Shares or any securities of the Company's subsidiaries;

          (iv) the entering into by the Company or any of its subsidiaries of
     any new line of business;

          (v) the manner in which the shares or other interests of any
     subsidiary or entity owned by the Company shall be voted at shareholders'
     or equivalent meetings of any such subsidiary or entity with respect to any
     matter of the type covered by this Section 3;

          (vi) any amendments, modifications, waivers or changes to or
     terminations of (A) any of the concessions/licenses granted by the Mexican
     authorities to conduct the main business of the Company, (B) the Company
     Bylaws, (C) any of the following, in each case as in effect on the date
     hereof, (1) any employment, consulting, confidentiality or non-competition
     agreement between the Company (or any of its subsidiaries) and any officer
     or key employee of the Company (or any of its subsidiaries), (2) any Grupo
     VAC Agreement, (3) this Agreement (including, without limitation, the
     Company Guidelines attached hereto as Exhibit B), (4) the Security Trust
     Agreement, or (5) the CPO Investment Trust Agreement, (D) any other
     instruments or agreements to which the Company is a party entered into as
     of or after the date hereof which were submitted for approval pursuant to
     Section 3(a), or (E) any other agreements to which the Company is a party
     entered into after the date of approval of the Company Bylaws by the
     Securityholders, the amendment of which would require approval under
     Section 3(a) if such agreement were in effect on the date hereof;

          (vii) the subdivision or combination in any way of the outstanding
     Shares of 1 (one) class or series of Shares of the Company or any of its
     subsidiaries, unless the outstanding Shares of the other class or series of
     Shares of the Company or its subsidiary, as applicable, shall also be
     proportionately subdivided or combined in a similar manner;


                                       11

<PAGE>

          (viii) except as provided in Section 5(j), granting to any Person the
     right to request the Company to register any Shares; provided, however,
     that the Company may grant rights to other Persons to participate in
     piggyback registrations so long as such rights are subordinate in all
     respects to the rights of Investors set forth herein;

          (ix) any commitment or agreement to do any of the foregoing; and

          (x) any of the matters set forth in Section 3(d) below.

     (c) Grupo VAC Key Matters. Subject to and conditioned upon compliance by
the Grupo VAC Investors and their respective Affiliates with the conditions set
forth in Section 5(m), the following subject-matters shall each be considered a
"Grupo VAC Key Matter" requiring special approval thereof as set forth in
Section 3(a):

          (i) the issuance of any Equity Securities of the Company or any of its
     subsidiaries for a per share price below US$0.3957 (as adjusted for stock
     splits, stock dividends, recapitalizations and similar events) other than
     (A) issuances of up to 28,368,087 shares (as adjusted for stock splits,
     stock dividends, recapitalizations and similar events) pursuant to existing
     stock options and management incentive plans of the Company shown on the
     Company's records (as of the date of the approval of these Bylaws by the
     Shareholders) as being reserved for future issuance pursuant to such stock
     options and existing management incentive plans and (B) issuances of Equity
     Securities as consideration for the acquisition of the assets or capital
     stock of 1 (one) or more companies;

          (ii) any amendments, modifications, waivers or changes to or
     terminations to (A) any of the concessions/licenses granted by the Mexican
     authorities to conduct the main business of the Company, (B) the Company
     Bylaws (but only to the extent such amendment is an amendment (1) to the
     definition of Grupo VAC Threshold Percentage, (2) to Section 11(a), 11(c)
     and/or 11(d) of the Company Bylaws or (3) that is otherwise material and
     adverse to the rights of the Grupo VAC Investors under these Bylaws), or
     (C) any of the Grupo VAC Agreements which would have a material adverse
     effect on the rights of the Grupo VAC Investors thereunder;

          (iii) any commitment or agreement to do any of the foregoing; and

          (iv) any of the matters set forth in Section 3(d) below.

     (d) Nexus and Grupo VAC Key Matters. The following subject-matters shall
each be considered as both a Nexus Key Matter and, subject to and conditioned
upon compliance by the Grupo VAC Investors and their respective Affiliates with
the conditions set forth in Section5(m), a Grupo VAC Key Matter requiring
special approval thereof as set forth in Section 3(a):

          (i) any assignment by the Company or any of its subsidiaries for the
     benefit of creditors or the voluntary commencement of any proceeding
     relating to the Company or any of its subsidiaries under any bankruptcy,
     reorganization, insolvency, suspension of payments, dissolution or
     liquidation law of any jurisdiction;


                                       12

<PAGE>

          (ii) the entering into by the Company or any of its subsidiaries, or
     amendment of the material terms of, any transaction or series of related
     transactions with any of the Company's officers, directors, employees,
     bondholders, shareholders, or any of their respective Affiliates or any
     individual related by blood or marriage to any such Person or any Person in
     which any such Person owns a beneficial interest or any Affiliate of any of
     the foregoing (collectively, "Restricted Persons"), other than any such
     transaction or series of related transactions involving (A) the issuance of
     debt or equity securities in which the Grupo VAC Investors are given a
     pre-emptive participation right to purchase their pro rata share of any
     such securities, (B) U.S. $1,000,000 (one million U.S. dollars) or less in
     the aggregate over the term of such transaction(s), or (C) customary
     banking relationships, in the case of this clause (C) and clause (B) above,
     entered into in the ordinary course of business on an arm's length basis
     and on terms no less favorable than those available from a third party (in
     each case as determined by a Nexus Director);

          (iii) the election, appointment or removal of any of the following key
     executives of the Company or any of its subsidiaries: the Chief Executive
     Officer, the General Managers of any business units, the Chief Operating
     Officer, the Chief Financial Officer, the Director of Marketing or the
     Chief Engineer, or any other individual with a similar or more senior title
     or position, and the approval of salary, compensation and benefit or other
     similar plans for such key executives;

          (iv) the approval of the Company's and its subsidiaries' annual
     business plan and annual budget for each fiscal year (as approved,
     including any amendments or modifications thereto permitted by the Company
     Bylaws, the "Approved Plan"); the approval of any amendment to,
     modification of or expenditures in excess of such Approved Plan; and the
     approval to enter into any material transaction outside of the ordinary
     course of business and not contemplated in any Approved Plan; provided,
     however, that if the annual business plan and budget are not approved by
     the Board in accordance herewith then the annual business plan and budget
     for the immediately preceding year shall be the Approved Plan;

          (v) the entering into or amendment of any agreement which would (under
     any circumstance) restrict the Company's or any of its subsidiaries' right
     or ability to perform the provisions of the Company Bylaws or any
     agreements or instruments to which it is a party together with its
     Securityholders or to conduct its business as currently conducted or as
     proposed to be conducted at any time;

          (vi) the incurrence or assumption by the Company and/or any of its
     subsidiaries of any indebtedness (including capitalized lease obligations)
     or other liabilities (other than trade payables incurred in the ordinary
     course of business which are not past due), and the mortgaging, pledging or
     incurring of a lien, encumbrance or other restriction on any of the assets
     or properties of the Company and/or any of its subsidiaries exceeding U.S.
     $10,000,000 (ten million U.S. dollars) in the aggregate at any time then
     outstanding or the amendment of any loan agreement, credit agreement,
     debenture or related document in connection with any indebtedness
     (including capitalized leases) approved pursuant to this Section 3;


                                       13

<PAGE>

          (vii) subject to the limitations set forth in Section 3(e), the
     Transfer or other disposal of all or a significant portion of the assets or
     Equity Securities of the Company or any of its subsidiaries (including, but
     not limited to, any Shares held by the Company as treasury shares) by the
     Company or any of its subsidiaries in any form of transaction, or the
     merger, consolidation, spin-off, recapitalization, reorganization
     (including a change in the legal nature of the Company or any of its
     subsidiaries), dissolution or liquidation of the Company or any of its
     subsidiaries;

          (viii) the establishment by the Company or any of its subsidiaries of
     any subsidiary or the issuance by the Company or any of its subsidiaries of
     any loans or advances to, guarantees for the benefit of, or investments in,
     any Person other than a wholly-owned subsidiary (other than advance
     payments made to suppliers in the ordinary course of business not exceeding
     an aggregate of U.S. $2,000,000 (two million U.S. dollars) outstanding at
     any time);

          (ix) any redemption of Shares by the Company, other than a pro-rata
     redemption of Shares (without regard to class or series of Shares) held by
     all of the Securityholders; and

          (x) any commitment or agreement to do any of the foregoing.

For purposes of clarification, (A) the elimination of the above matters as Grupo
VAC Key Matters shall not affect the designation of such matters as Nexus Key
Matters and (B) the right described in Section 3(d)(ix) above is in addition to
the Nexus Key Matter right described in Section 3(b)(ii).

     (e) Grupo VAC Voting Limitations. Notwithstanding anything to the contrary
contained herein, neither the Grupo VAC Investors, the Grupo VAC Representative
nor the Grupo VAC Director shall have any rights pursuant to this Section 3 to
approve (i) any Qualified Public Offering (or any transactions undertaken in
connection with such a Qualified Public Offering), (ii) a Sale of the Company,
(iii) a Drag-Along Sale, (iv) subject to the Grupo VAC Investors' right of first
offer set forth in Section 5(g), any divesture by the BA Investors of all of
their beneficial and record ownership of Shares to any Person (or related
Persons), or (v) any action or decision by the Company under or with respect to
the Grupo VAC Agreements (e.g., the delivery of a notice or claim under the
Holdback Trust Agreement). In connection with any of the matters described in
clauses (i) through (v) of the preceding sentence, the Grupo VAC Investors and
their Permitted Transferees shall vote, and shall cause the Grupo VAC Director
to vote all of the Shares beneficially owned or owned of record by the Grupo VAC
and its Permitted Transferees in the same manner as the BA Investors vote their
Shares (and shall cause the Grupo VAC Director to vote such Shares in the same
way that the Nexus Director votes its Shares).

     (f) Additional Approvals. The Required Approvals set forth in this Section
3 are in addition to and shall in no way limit or otherwise affect the
obligation of the Company to also (i) submit to the Board for approval other
matters which are required to be submitted to the Board for approval by
applicable law or the Company Bylaws or this Agreement or (ii) obtain any
additional approvals which may be required by applicable law, the Company Bylaws
or this Agreement.

     (g) Grupo VAC Voting Rights Termination. The Grupo VAC Representative's,
the Grupo VAC Investors', and the Grupo VAC Director's rights under this Section
3 shall terminate upon the earliest to occur of (A) the consummation of a Sale
of the Company, (B) the consummation


                                       14

<PAGE>

of a Qualified Public Offering, (C) the percentage of the outstanding Shares
owned beneficially or of record by the Grupo VAC Investors becomes less than the
Grupo VAC Threshold Percentage and (D) the failure of the Grupo VAC Investors
and their respective Affiliates to comply with Section 5(m).

     SECTION 4. COVENANTS.

     (a) Financial Statements and Other Information. To the extent required in
writing, and subject in the case of the Grupo VAC Investors to their compliance
with Section 5(m), the Company shall deliver to each Investor and each Member of
the Board:

          (i) at least 30 (thirty) days, but not more than 90 (ninety) days,
     prior to the beginning of each fiscal year, a strategic business plan and
     budget, prepared on a monthly basis for the Company and its subsidiaries
     for such fiscal year (displaying anticipated statements of income, cash
     flows and balance sheets) and including investment requirements,
     assessments of the market, and 3-year financial projections;

          (ii) (A) promptly upon preparation thereof any significant budgets
     prepared by the Company and any revisions of the Approved Plan or other
     budgets; (B) within 20 (twenty) days after any monthly period, a report
     comparing actual performance against that month's budgetary projections
     contained in the Approved Plan and containing information and data
     reasonably requested by the Investors; and (C) within 20 (twenty) days
     after any monthly period in which there is a material adverse deviation
     from the Approved Plan, an officer's certificate explaining the deviation
     and what actions the Company has taken and proposes to take with respect
     thereto;

          (iii) as soon as available but not more than 30 (thirty) days after
     the end of each quarterly accounting period in each fiscal year, unaudited
     consolidating and consolidated statements of income and cash flows of the
     Company and its subsidiaries for such quarterly period and for the period
     from the beginning of the fiscal year to the end of such quarter, and
     unaudited consolidating and consolidated balance sheets of the Company and
     its subsidiaries as of the end of such quarterly period, setting forth in
     each case comparisons to the Approved Plan and to the corresponding period
     in the preceding fiscal year, and all such statements shall be prepared in
     accordance with Mexican generally accepted accounting principles and shall
     be certified by an officer of the Company;

          (iv) (A) accompanying the financial statements referred to in Section
     4(a)(iii), an officer's certificate stating that (1) there is no material,
     continuing breach by the Company or, to the best knowledge of the Company,
     by any Securityholder under this Agreement and that neither the Company nor
     any of its subsidiaries is in default under any of its other material
     agreements, the concession/license granted by the Mexican government to
     conduct the Business or the Guidelines and (2) the Company and its
     Subsidiaries have fully complied with the laws referenced in this Section
     4(a) and Section 4(b), including the United States Foreign Corrupt
     Practices Act (the "FCPA"), and/or (B) promptly (but, in any event, within
     five business days) after the discovery or receipt of notice of any
     material, continuing breach by the Company or, to the best knowledge of the
     Company, by any Securityholder under this Agreement, any noncompliance with
     the FCPA, any default under any material agreement to which it or any of
     its subsidiaries is a party which is not cured within 5 (five) days, any


                                       15

<PAGE>

     condition or event which is reasonably likely to result in any material
     liability under any federal, state or local statute or regulation relating
     to public health and safety, worker health and safety or pollution or
     protection of the environment or any other material adverse change, event
     or circumstance affecting the Company or any subsidiary (including, without
     limitation, the filing of any material litigation against the Company or
     any subsidiary or the existence of any dispute with any Person which
     involves a reasonable likelihood of such litigation being commenced), an
     officer's certificate specifying the nature and period of existence
     thereof, and what actions the Company and its subsidiaries have taken and
     propose to take with respect thereto;

          (v) within 90 (ninety) days after the end of each fiscal year (with
     respect to financial statements prepared in accordance with Mexican
     generally accepted accounting principles) and 120 (one hundred and twenty)
     days after the end of each fiscal year (with respect to United States
     generally accepted accounting principles), consolidating and consolidated
     statements of income and cash flows of the Company and its subsidiaries for
     such fiscal year, and consolidating and consolidated balance sheets of the
     Company and its subsidiaries as of the end of such fiscal year, setting
     forth in each case comparisons to the Approved Plan and to the preceding
     fiscal year, all prepared in accordance with both Mexican and United States
     generally accepted accounting principles (together with a reconciliation
     thereof) and accompanied by (A) with respect to the consolidated portions
     of such statements, an opinion of PricewaterhouseCoopers S.C. (Mexico) or
     another independent accounting firm acceptable to Nexus, which opinion
     contains no qualifications that relate to limitations on the scope of the
     audit, an adverse condition with respect to the Company, or an adverse act
     by the Company, excluding currency devaluations, force majeure events and
     acts of god, (B) a certificate from such accounting firm, addressed to the
     Board, stating that in the course of its examination nothing came to its
     attention that caused it to believe that there was a default by the Company
     or any subsidiary in the fulfillment of or compliance with any of the
     terms, covenants, provisions or conditions of any material agreement to
     which the Company or any subsidiary is a party or, if such accountants have
     reason to believe any such default by the Company or any subsidiary exists,
     a certificate specifying the nature and period of existence thereof, and
     (C) a copy of such firm's annual management letter to the Board;

          (vi) promptly upon receipt thereof, any additional reports, management
     letters or other detailed information concerning significant aspects of the
     Company's operations or financial affairs given to the Company by its
     independent accountants (and not otherwise contained in other materials
     provided hereunder);

          (vii) within 10 (ten) days after transmission thereof, copies (in
     English) of all financial statements, proxy statements, reports and any
     other general written communications which the Company sends to its
     shareholders and copies of all registration statements and all regular,
     special or periodic reports (other than those related solely to routine
     technical matters) which it files, or any of its officers or directors
     file, with respect to the Company, with the Bureau, the National Banking
     and Securities Commission and the Ministry of Communications and
     Transportation or the U.S. Securities and Exchange Commission or with any
     securities exchange on which any of its securities are then listed, and
     copies of all press releases and other statements made available generally
     by the


                                       16

<PAGE>

     Company to the public concerning material developments in the Company's and
     its subsidiaries' businesses; and

          (viii) with reasonable promptness, such other information and
     financial data concerning the Company and its subsidiaries as any Person
     entitled to receive information under this Section 4(a) may reasonably
     request in connection with the monitoring of their investment in the
     Company or their activities as a member of the Board.

     Each of the financial statements referred to in Sections 4(a)(iii) and
4(a)(v) shall be true and correct in all material respects as of the dates and
for the periods stated therein, subject in the case of the unaudited financial
statements to changes resulting from normal year-end adjustments for recurring
accruals (none of which would, alone or in the aggregate, be materially adverse
to the condition (financial or otherwise), operating results, assets, operations
or business prospects of the Company and its subsidiaries taken as a whole).

     The Grupo VAC Investor's rights under this Section 4 are subject to and
conditioned upon compliance by the Grupo VAC Investors and their respective
Affiliates with the conditions set forth in Section 5(m).

     All financial statements and other deliveries required under this Section
4(a) shall be expressed in both U.S. dollars and Mexican pesos (or the then
current Mexican currency).

     (b) Compliance with U.S. Foreign Corrupt Practices Act. The Company shall,
and shall cause each of its subsidiaries to at all times cause to be done all
things necessary to, comply with (and, upon the request of Nexus from time to
time, provide evidence to the Investors of the Company's and its subsidiaries'
compliance with) the U.S. Foreign Corrupt Practices Act.

     (c) Inspection of Property. The Company shall permit any representative
designated by a member of the Board at such times as any such Person may
reasonably request during regular business hours after prior written notice of
at least 2 (two) business days to (i) visit and inspect any of the properties of
the Company and its subsidiaries, (ii) examine and copy the corporate and
financial records of the Company and its subsidiaries, and (iii) discuss the
affairs, finances and accounts of the Company and its subsidiaries with the
directors, officers, key employees and independent accountants of the Company
and its subsidiaries.

     (d) Confidentiality. Each Securityholder agrees that it shall use its
reasonable efforts to, and shall use its reasonable efforts to cause its
respective directors, officers, employees, former employees, advisors and
Affiliates to, keep confidential any information or materials which (i) pertain
to the Company or its subsidiaries or their respective businesses or (ii)
pertain to matters designated as proprietary and confidential by the Company
(collectively, "Confidential Information"); provided, however, that (A) any
Confidential Information required by law, regulators or legal or administrative
process to be disclosed may be disclosed without violating the provisions of
this Section 4(d), (B) the Securityholders may disclose Confidential Information
to their respective directors, officers, employees, former employees, advisors,
investors, equity owners and Affiliates ("Affiliated Parties") and their
respective Affiliated Parties if the disclosing party believes that such
disclosure is necessary or desirable in connection with the monitoring of such
Securityholders investment in the Company; provided, however, that such
Affiliated Party must comply with the terms and provisions of this Section 4(d)
as if they were named as a party for


                                       17

<PAGE>

purposes hereto in lieu of the Securityholder, (C) the Securityholders (or any
of their Affiliated Parties and their respective Affiliated Parties) may
disclose Confidential Information in connection with the Transfer of any portion
of Shares so long as such Person's transferee agrees in writing to be bound by
the provisions hereof; provided, however, that such sale or transfer does not
violate any provisions of this Agreement, and (D) this Section 4(d) shall not
prohibit the Securityholders from disclosing any Confidential Information that
is available to the public on the date hereof, or which thereafter becomes
available to the public other than as a result of a breach of this Section 4(d);
provided, however, that such Confidential Information may not be disclosed until
it has, in fact, become available to the public other than as a result of a
disclosure by the Securityholders or its Affiliated Party in violation of this
agreement. Each of the Securityholders agrees and acknowledges that Confidential
Information constitutes "industrial secrets" within the meaning of the Mexican
Intellectual Property Law and is entitled to all of the protections afforded the
Company by such law.

     (e) UBTI. Notwithstanding any provision of this Agreement to the contrary
the Company shall not undertake any activity, operate any trade or business, or
take any action, including without limitation the borrowing of money or the
incurring of any other indebtedness, obligation, or liability, that would cause
any Securityholder, any partner of any Securityholder, or any Person owning,
directly or indirectly, any interest in a Securityholder or the Company, whose
income is exempt from United States federal income tax (each, an "Affected
Person"), to have or incur any unrelated business taxable income (as defined in
Sections 511 through 514 of the United States Internal Revenue Code) on account
of such activity or action without the express prior written consent of each
Securityholder who is (or is acting on behalf of) an Affected Person, which
consent may be granted, withheld or conditioned in such Securityholder's
respective sole and absolute discretion.

     (f) Shareholders Meetings. Any Shareholders meeting shall be called and
conducted in compliance with the applicable provisions of the Company's Bylaws.

     SECTION 5. RESTRICTIONS ON TRANSFER OF SHARES.

     (a) Transfer of Shares. No Securityholder shall Transfer any Shares (or any
interest therein) or Options (or any interest therein) except pursuant to the
provisions of this Section 5. Any Transfer in violation of this Section 5 shall
be null and void ab initio and shall not be consented to, recognized or
registered by the Company for any purpose.

     (b) Restricted Shares. Except for Transfers to (i) Permitted Transferees,
(ii) pursuant to a Sale of the Company or (iii) of Shares registered in a Public
Offering (collectively, the Exempt Transfers), no Securityholder shall Transfer
any Series A Shares or Series B Shares (the "Restricted Shares"), without the
prior written approval of Nexus, solely in its capacity as a Securityholder (and
without any fiduciary duty to the Company or any of the Company's
Securityholders) which consent may be withheld for any reason or no reason (the
"Restricted Share Transfer Consent"). If the Restricted Share Transfer Consent
is obtained with respect to a proposed Transfer, the transferring holder of such
Restricted Shares shall also comply with the requirements of Sections 5(c) (if a
Non-Investor), 5(d) (if an Investor), 5(e), 5(f) and 5(g).


                                       18
<PAGE>

     (c) Rights of First Refusal on Transfers by Non-Investors. Except for an
Exempt Transfer, at least 30 (thirty) days prior to any Transfer of any Shares
by any Securityholder other than an Investor (the "Transferring Non-Investor
Securityholders"):

          (i) Such Securityholder shall deliver written notice thereof (the
     "Offer Notice") to the Secretary of the Board who shall then promptly
     deliver such Offer Notice (but in any event within 5 (five) days) to each
     of the other Securityholders (other than the CPO Trustee) (the "Non-CPO
     Securityholders"), at the registered addresses of such Securityholders on
     file with the Company, disclosing the number of Shares to be Transferred,
     the proposed price, terms and conditions of the Transfer and the identity
     of the prospective transferee(s) who would acquire such Shares (if known at
     such time).

          (ii) The Non-CPO Securityholders may elect to purchase all (but not
     less than all) of the Shares to be Transferred on the same terms and
     conditions as those set forth in the Offer Notice. Each Non-CPO
     Securityholder desiring to participate shall give written notice within 30
     (thirty) days after the Offer Notice has been given to the Secretary of the
     Board to the Transferring Non-Investor Securityholder of the maximum number
     of Shares that such Non-CPO Securityholder desires to purchase. If the
     Non-CPO Securityholders elect to purchase all such Shares thereunder, the
     Transfer of such Shares shall be consummated as soon as possible after the
     delivery of the purchase election notice(s) to the transferring Investor,
     but in no event later than 15 (fifteen) days after the expiration of such
     30-day right of first refusal election period. If the aggregate number of
     Shares desired to be purchased by participating Non-CPO Securityholders
     exceeds the number of Shares to be Transferred pursuant to the Offer
     Notice, each Non-CPO Securityholders shall be entitled to purchase a pro
     rata number of Shares based on the Shares held by each such participating
     Non-CPO Securityholder.

          (iii) If, within 30 (thirty) days after the delivery of the Offer
     Notice, the Non-CPO Securityholders have not elected to purchase all of the
     Shares specified in the Offer Notice, the Transferring Non-Investor
     Securityholders may Transfer the Shares specified in the Offer Notice to
     the transferee(s) specified in the Offer Notice at a price and on terms no
     more favorable to the transferee(s) than are specified in the Offer Notice
     for a period of no more than 90 (ninety) days after the 30th day after
     delivery of the Offer Notice (the "RFR Free Transfer Period"). Any Shares
     not Transferred within such 90-day period shall remain subject to the
     provisions of this Section 5(c).

          (iv) If an electing Securityholder is not permitted under applicable
     Mexican law to hold the amount or type of Shares which such electing
     Securityholder would be otherwise entitled to purchase upon the exercise of
     its rights under this Section 5(c) (e.g. because such Securityholder is not
     Mexican), then such electing Securityholder may designate another purchaser
     who is qualified under Mexican law to purchase such Shares or, at its
     election, such electing Securityholder may request the Company to agree (to
     the extent permitted under Mexican law) to exchange such Shares to be
     purchased by such electing Securityholder (pursuant to the exercise of its
     rights under this Section 5(c)) for other securities of the Company which
     such Securityholder is permitted to purchase and which have identical
     rights as such Shares being transferred; provided, however, that, in order
     to


                                       19

<PAGE>

     comply with applicable law, the voting rights of such securities may be
     limited to the minimum level necessary to effect such compliance.

     (d) Right of First Offer on Transfers by Investors (other than BA
Investors).

          (i) Except for an Exempt Transfer or a Transfer to a Grupo VAC
     Investor pursuant to its exercise of rights under Section 5(g), if any
     Investor other than a BA Investor desires to transfer any Shares, such
     Investor shall deliver written notice thereof (the "Investor Transfer
     Notice") to the Secretary of the Board who shall, within 3 (three) business
     days, deliver a copy thereof to each Investor holding at least 1% of the
     Shares then outstanding (a "Qualified Investor"), at the registered
     addresses of such Qualified Investor on file with the Company, disclosing
     the type and number of Shares sought to be transferred, the proposed price
     of the Transfer and other material economic terms of the proposed Transfer.

          (ii) The Qualified Investors may elect to purchase all (but not less
     than all) such Shares to be Transferred on a pro rata basis (determined on
     the basis of number of Shares held by each such Qualified Investor) and at
     the same price specified in the Investor Transfer Notice. Each Qualified
     Investor desiring to participate shall give written notice to such
     transferring Investor within 30 (thirty) days after the Investor Transfer
     Notice has been given to the Secretary of the Board of the maximum number
     of Shares that such Qualified Investor desires to purchase. If the
     Qualified Investors elect to purchase all such Shares thereunder, the
     Transfer of such Shares shall be consummated as soon as possible after the
     delivery of the purchase election notice(s) to the transferring Investor,
     but in no event later than 30 (thirty) days after delivery of the
     applicable purchase election notice. If the aggregate number of Shares
     required to be purchased by participating Qualified Investors exceeds the
     number of Shares to be Transferred pursuant to the Investor Transfer
     Notice, each Qualified Investor shall be entitled to purchase a pro rata
     number of Shares based on the Shares held by each such participating
     Qualified Investor.

          (iii) If the electing Qualified Investors have not elected to purchase
     all of the Shares specified in the Investor Transfer Notice, the
     transferring Investor may, for a period (the "ROFO Free Transfer Period")
     of 180 days after the expiration of such period, Transfer the Shares
     specified in the Investor Transfer Notice to 1 (one) or more parties at a
     price and on other material economic terms no more favorable to the
     transferees thereof than as set forth in the Investor Transfer Notice. Any
     such Shares specified in the Investor Transfer Notice that are not
     transferred within such 180-day period shall remain subject to the
     provisions of this Section 5(d).

          (iv) If an electing Qualified Investor is not permitted under
     applicable Mexican law to hold the amount or type of Shares to which such
     electing Qualified Investor would be otherwise entitled to purchase upon
     the exercise of its rights under this Section 5(d), then such electing
     Qualified Investor may designate another purchaser who is qualified under
     Mexican law to purchase such Shares or, at its election, such electing
     Qualified Investor may request the Company to agree (to the extent
     permitted under Mexican law) to exchange such Shares to be purchased by
     such electing Qualified Investor (pursuant to the exercise of its rights
     under this Section 5(d)) for other securities of the Company which such
     Qualified


                                       20

<PAGE>

     Investor is permitted to hold and which have identical rights as those
     being Transferred; provided, however, that, in order to comply with
     applicable law, the voting rights of such securities may be limited to the
     minimum level necessary to effect such compliance.

     (e) Participation (Tag-Along) Rights in Transfers.

          (i) If a Securityholder desires to Transfer any Shares (a
     "Transferring Securityholder") other than pursuant to an Exempt Transfer,
     which shall be governed by Sections 5(f), 5(h), 5(i), 5(j) and 5(l) as
     applicable, such Securityholder shall deliver written notice thereof (the
     "Tag-Along Right Notice") to the Secretary of the Board, and the Secretary
     of the Board shall then promptly (but in any event within 5 (five) days or,
     to the extent necessary to comply with requirements of applicable law, such
     longer period as reasonably determined by the Board (including the approval
     of at least 1 (one) Nexus Director)) deliver to the other Securityholders
     (other than the CPO Trustee unless such Transfer constitutes a Sale of the
     Company, in which case the CPO Trustee shall be entitled to receive notice
     of and participate in such Transfer), at the registered addresses of such
     Securityholders on file with the Company, such Tag-Along Right Notice
     (which notice may be given simultaneously with any notice required to be
     delivered pursuant to Sections 5(c), 5(d), and 5(g) above), disclosing the
     number of Shares to be Transferred, the proposed price, terms and
     conditions of the Transfer (including, without limitation, a description of
     any expense, escrow, holdback, earn-out, indemnity or similar obligations
     to which the participating Securityholders shall be responsible), the
     identity of the prospective transferee(s) (if known at such time) and
     whether such Securityholder's participation right is subject to adjustment
     as a result of Sections 5(c), 5(d) or 5(g) (i.e., the tag-along rights
     shall only apply to the Shares that the Transferring Securityholder is
     entitled to Transfer after first complying with the requirements of Section
     5(c), 5(d), or 5(g), as applicable).

          (ii) All eligible Securityholders (other than the CPO Trustee unless
     such Transfer constitutes a Sale of the Company) may elect to participate
     on a pro rata basis (based on the number of Shares) in the contemplated
     Transfer described in the Tag-Along Right Notice by giving written notice
     to the Transferring Securityholder within the longer of (i) 20 (twenty)
     days after delivery of the Tag-Along Right Notice to the Company or (ii) 3
     (three) business days after the beginning of the RFR Free Transfer Period,
     if applicable (the "Tag-Along Window"). Each such Securityholder may
     participate in the contemplated Transfer at the same price and, subject to
     clause (vi) below, on the same terms specified in the Tag-Along Right
     Notice; provided, however, that if a Securityholder holds more than 1 (one)
     class or series of Shares, such Securityholder's rights under this Section
     5(e) to participate in such Transfer shall be allocated proportionately
     among all of the Shares owned by such Securityholder (e.g. if a Transfer
     pursuant to a Tag-Along-Right Notice is contemplated, a Securityholder
     holding 1,000 Series B Shares and 1,000 Series N Shares would be required
     to Transfer an equal number of both Series B and Series N Shares). The
     failure to deliver notice electing to participate within a Tag-Along Window
     shall be deemed an automatic and complete waiver of all rights to
     participate in such Transfer pursuant to this Section 5(e). In connection
     with any Transfer, each Securityholder's participation rights therein (with
     respect to the absolute number of Shares) is subject to adjustment as a
     result of Sections 5(c), 5(d), and 5(g) (i.e., the tag-along rights shall
     only apply to the Shares that the Transferring


                                       21

<PAGE>

     Securityholder is entitled to Transfer after first complying with the
     requirements of Sections 5(c), 5(d), and 5(g)).

          (iii) If no Securityholder elects to participate in the contemplated
     Transfer (either by giving notice to such effect or failing to give notice
     within the Tag-Along Window), then, pursuant to and on the terms
     substantially as described in the Tag-Along Right Notice, the Transferring
     Securityholder may Transfer such Shares to the Person(s) specified in the
     Tag-Along Right Notice for a period equal to (A) the remaining RFR Free
     Transfer Period, if applicable, (B) the remaining ROFO Free Transfer
     Period, if applicable, (C) 180 days after the expiration of the Tag-Along
     Window if the proposed Transfer described in the Tag-Along Notice is
     pursuant to Section 5(g) or (D) 120 days after the expiration of the
     Tag-Along Window if the proposed Transfer of Shares described in the
     Tag-Along Notice was not subject to Sections 5(c), 5(d), or 5(g); provided,
     however, that there will be an automatic 60-day extension of such 120-day
     period to the extent that regulatory approvals for a Transfer have not been
     obtained within such original 120-day period. If the Transferring
     Securityholder fails to Transfer such Shares described in the Tag-Along
     Notice within such applicable period, the Transferring Securityholder shall
     not Transfer such Shares without again complying with the provisions of
     this Section 5(e).

          (iv) No Transferring Securityholder shall Transfer any of its Shares
     to any prospective transferee if such prospective transferee declines to
     allow the participation of the other Securityholders on the terms provided
     in this Section 5(e), unless and only to the extent that the prospective
     transferee may not hold such other Securityholder's Shares because of
     ownership restrictions on such Shares imposed by this Agreement or
     applicable Mexican law.

          (v) The rights of Securityholders to participate in a Transfer as set
     forth in this Section 5(e) are subject to the satisfaction of the following
     conditions: (A) each participating Securityholder will only be required to
     make affirmative representations and warranties only as to (1) due power
     and authority to enter into the agreement and transactions contemplated
     thereby, (2) non-contravention of any agreement to which it is a party or
     by which it is bound, and (3) good and valid title to the equity securities
     to be transferred (or, in the case of beneficial ownership of the Shares
     through a trust, good and valid title to the certificates of participation
     in such trust), free and clear of any and all liens, claims, pledges,
     options and restrictions of any kind whatsoever (other than as contemplated
     hereby and by this Agreement), (B) the participating Securityholders shall
     be severally obligated to share, on a pro rata basis (based on such
     Securityholder's share of the aggregate proceeds paid with respect to the
     Shares sold in such transaction), any expense, escrow, holdback, earn-out,
     indemnity or similar obligation that the Transferring Securityholder has
     agreed to in connection with such Transfer (but, with respect to each
     participating Securityholder, not in excess of the consideration such
     Securityholder is entitled to receive in connection with its participation
     in the transaction), and with respect to any contingent post-closing
     indemnity or other obligations, any proceeds a Securityholder is entitled
     to receive in connection with its participation pursuant to this Section
     5(e) in a Transfer shall be subject to a holdback obligation unless such
     Securityholder provides such purchaser with assurances and/or collateral,
     in form and substance satisfactory to such purchaser, as such purchaser may
     require; provided, however, that any assurances or collateral provided by
     the Transferring


                                       22

<PAGE>

     Securityholder and/or the other participating Securityholders may differ
     from Securityholder to Securityholder (it being understood and permitted,
     that certain Securityholders (including, without limitation, the BA
     Investors and/or the Grupo VAC Investors) may only be required to sign an
     agreement or indemnity without any holdback obligations), and (C) if the
     purchaser of the Shares requires the Transferring Securityholder and the
     other participating Securityholders to execute any ancillary purchase or
     other agreements, each participating Securityholder shall be required, as a
     condition to its participation rights in such Transfer, to execute all such
     agreements, subject to the requirements set forth in the preceding
     sentence; provided, however, that in no event shall any Securityholder be
     required to execute a non-competition or non-solicitation agreement.

          (vi) To the extent that a Securityholder holds Shares subject to
     restrictions on ownership pursuant to this Agreement or applicable Mexican
     law (e.g., Series A Shares may only be owned by Mexicans), such
     Securityholder will only be eligible to Transfer such restricted Shares
     pursuant to this Section 5(e) to purchasers who are eligible to own such
     restricted Shares.

          (vii) The CPO Trustee is not entitled to participate pursuant to the
     tag-along rights in this Section 5(e) in any Transfer other than a Transfer
     that constitutes a Sale of the Company.

          (viii) The tag-along rights in this Section 5(e) shall not apply to a
     Drag-Along Sale.

     (f) Drag Along Rights.

          (i) If, at any time or from time to time, Nexus and/or Bank of America
     desires that Maxcom and its Securityholders approve and consummate a Sale
     of the Company (and regardless of the percentage of outstanding Shares then
     owned or proposed to be sold by the BA Investors in such Sale of the
     Company so long as the percentage of the BA Investors' Shares proposed to
     be included in any such Sale of the Company is proportional to the
     percentage of each other Securityholder's Shares proposed to be included in
     such Sale of the Company prior to giving effect to any restrictions on
     non-Mexican ownership of Shares (e.g., if the BA Investors propose to sell
     51% of their Shares, each of the other Securityholders shall be required to
     sell 51% of such Securityholders' Shares)), Nexus and/or Bank of America
     may so elect to require Maxcom and its Securityholders to consummate and
     approve the terms and conditions of a "Drag-Along Sale". In connection with
     any Drag-Along Sale, (1) the Grupo VAC Investors shall have the rights of
     first offer set forth in Section 5(g) and (2) regardless of whether such
     Drag-Along Sale is to the Grupo VAC Investors or another purchaser:

               (A) The Company shall cooperate with Nexus and Bank of America
          and take all actions in connection with the consummation of the
          Drag-Along Sale as requested by the Board, Nexus or Bank of America,
          including, without limitation, retaining such legal and financial
          advisors (including, without limitation, investment bankers, as may
          deemed necessary or appropriate by Nexus and/or Bank of America
          (and/or the Board) to assist the Company in structuring and
          consummating such Drag-Along Sale (and, if requested by Nexus or Bank
          of America, the Company and


                                       23

<PAGE>

          such advisors shall conduct an auction of the Company by contacting
          multiple prospective purchasers to consummate a Sale of the Company).

               (B) At the request of Nexus and/or Bank of America, each of the
          Company's Securityholders and the beneficial owners of Shares shall
          (and shall cause any director on the Board designated by such
          Securityholder to) vote in favor of, consent to and raise no
          objections against such Drag-Along Sale and the Company and each
          Securityholder (other than the CPO Trustee) and beneficial owner of
          Shares shall take all other actions in connection with the
          consummation of the Drag-Along Sale as requested by the Board, Nexus
          or Bank of America including entering into purchase agreements,
          carrying out due diligence, calling Securityholder meetings, voting in
          favor, proxies, and exercising and/or terminating all options.

               (C) If the Drag-Along Sale is structured as (i) a merger or
          consolidation of the Company, or other transaction triggering
          Securityholder rights, then each Securityholder shall waive any
          dissenters' rights or similar rights in connection with such merger or
          consolidation (and each optionholder shall be required to exercise or
          consent to the cancellation of any of its Options in connection with
          such Drag-Along Sale) or (ii) as a sale of Shares, then, in each case,
          each Securityholder shall agree to sell all (or, in the case of a
          Drag-Along Sale of less than all of the Shares, its pro rata share) of
          its Shares and, to the extent included in a Drag-Along Sale, rights to
          acquire Shares. The Company shall use its best efforts to cause each
          Option, unless exercised prior to the consummation of a Drag-Along
          Sale, to be cancelled immediately prior to the consummation of a
          Drag-Along Sale without any additional consideration required to be
          paid therefor, and in connection therewith, each Securityholder
          holding any Options shall consent to such a cancellation of any
          Options it holds in connection with a Drag-Along Sale (i.e., to the
          extent not exercised prior to the consummation of such Drag-Along
          Sale).

               (D) Each beneficial owner of Shares, other than any holder of
          CPOs, shall use its best efforts to cause the voting power of its
          Shares to be voted for (or to consent to) a Drag-Along Sale.

               (E) In connection with a Drag-Along Sale:

                    (i) The obligations of the Securityholders with respect to
               the Drag-Along Sale are subject to the receipt by each
               Securityholder of its pro rata share of the aggregate
               consideration payable to all Securityholders and in-the-money
               optionholders in such Drag-Along Sale.

                    (ii) In connection with a Drag-Along Sale, (A) each
               Securityholder (including the CPO Trustee) will be required to
               make affirmative representations and warranties only as to (1)
               due power and authority to enter into the agreement and
               transactions contemplated thereby, (2) non-contravention of any
               agreement to which it is a party or by which it is bound, and (3)
               good and valid title to the Shares to be Transferred, free and
               clear of any and all liens, claims, pledges, options and
               restrictions of any kind whatsoever (other than as set forth
               herein) and (B) the Securityholders and


                                       24

<PAGE>

               any in-the-money optionholders shall be severally obligated to
               share, on a pro rata basis (based on such holder's share of the
               aggregate proceeds paid with respect to the Shares and
               in-the-money Options in such Drag-Along Sale) in any expense,
               escrow, holdback, earn-out, indemnity or similar obligation that
               Nexus or the Company has agreed to in connection with such
               Drag-Along Sale (but, with respect to each participating
               Securityholder and optionholder, not in excess of the
               consideration such holder is entitled to receive in connection
               with its participation in the Drag-Along Sale), and with respect
               to any contingent post-closing indemnity or other obligations,
               any proceeds a Securityholder or optionholder is entitled to
               receive in connection with a Drag-Along Sale shall be subject to
               a holdback obligation unless such holder provides such purchaser
               with assurances and/or collateral, in form and substance
               satisfactory to the purchaser in such Drag-Along Sale; provided,
               however, that any assurances or collateral provided by Nexus
               and/or the other participating Securityholders and optionholders
               may differ from holder to holder (it being understood and
               permitted that certain Securityholders (including, without
               limitation, the BA Investors and/or the Grupo VAC Investors) and
               optionholders may only be required to sign an agreement or
               indemnity without any holdback obligations), and (C) Company and
               each participating Securityholder shall cooperate with Bank of
               America and Nexus and take such additional action as may be
               requested by Bank of America or Nexus or as required by
               applicable law. If the purchaser in a Drag-Along Sale requires
               Nexus and the other participating Securityholders and
               optionholders to execute any ancillary purchase or other
               agreements, each such participating holder (other than with
               respect to the CPO Trustee) shall be required to execute all such
               agreements, subject to the requirements set forth in the
               preceding sentence.

                    (iii) To the extent that a Securityholder holds Shares
               subject to restrictions on ownership pursuant to this Agreement
               or applicable Mexican law, it will only be obligated to Transfer
               to purchasers who are eligible to own such restricted Shares;
               provided, however, that in connection with a Drag-Along Sale, the
               purchaser shall have the right to assign its right to purchase
               such restricted Shares to a different purchaser who is eligible
               to own such restricted Shares (for the same consideration and on
               the same terms and conditions (other than as to restrictions on
               ownership) as the other Shares being sold in the Drag-Along
               Sale).

     (g) Grupo VAC Right of First Offer on Certain Transfers and Limited Offer
Right on Certain Sale of Company Transactions.

          (i) So long as (A) the Grupo VAC Investors at such time collectively
     own at least the Grupo VAC Threshold Percentage of the issued and
     outstanding Shares, (B) a ROFO-RLO Free Period is not then in effect, (C)
     the Grupo VAC Director (and its alternate), the Grupo VAC Representative,
     the Grupo VAC Investors, their respective Affiliates, and, to the extent
     applicable under Section 5(g)(xi), their respective representatives and
     agents, have complied (and are complying) with the Recusal


                                       25

<PAGE>

     requirements set forth in Section 5(g)(xi) and (D) the Grupo VAC
     Representative's and the Grupo VAC Investors' rights under this Section
     5(g) have not been terminated pursuant to Section 5(g)(vi) or Section 5(n)
     (collectively, the "Grupo VAC Offer Right Conditions"), if Nexus or Bank of
     America is considering or desires to (1) Transfer all of the Shares owned
     beneficially or of record by the BA Investors to any Person (or related
     Persons) other than (x) to a Permitted Transferee or other Qualified
     Affiliate of Bank of America or (y) a Transfer only of Shares registered in
     a Public Offering, (2) Nexus or Bank of America desires to exercise its
     rights under Section 5(f) to cause a Drag-Along Sale or (3) approve a sale
     for cash of all or substantially all of the consolidated assets of the
     Company, Nexus and/or Bank of America shall first deliver written notice of
     such proposed action ("Grupo VAC ROFO Notice") to the Grupo VAC
     Representative, disclosing the type and number of Shares sought to be
     Transferred and other material economic terms of the proposed Transfer (or
     if such transaction is a sale of all or substantially all of the
     consolidated assets of the Company, a description of the material economic
     terms of such proposed sale), including whether or not such proposed
     Transfer (or asset sale, as applicable) is in connection with an offer from
     a third-party to acquire such Shares or assets that was not solicited by
     the Company, Nexus or Bank of America (an "Unsolicited Transfer").

          (ii) For purposes of this Section 5(g), a "ROFO-RLO Free Period" shall
     exist if the Company, Nexus and/or Bank of America delivers a Grupo VAC
     ROFO Notice or a Grupo VAC RLO Notice and either (1) the Grupo VAC
     Representative declines or otherwise fails to deliver a valid Grupo VAC
     Offer or Grupo VAC Limited Offer, as the case may be or (2) Nexus rejects,
     declines or otherwise does not accept such Grupo VAC Offer or Grupo VAC
     Limited Offer; provided, however, for purposes of clarification, that the
     conditions in Section 5(g)(iv) and 5(g)(v) shall continue to apply to a
     rejected Grupo VAC Offer during the ROFO-RLO Free Period. The length of the
     ROFO-RLO Period shall be (A) 180 days following the date of rejection of a
     Grupo VAC Offer, (B) 210 days following the delivery of the Grupo VAC ROFO
     Notice if the Grupo VAC Representative does not deliver a valid Grupo VAC
     Offer (or otherwise fails to comply with Section 5(g)(iv)) and (C) 210 days
     following the delivery of a Grupo VAC RLF Notice if (x) Bank of America,
     Nexus and the BA Investors decline to accept for any reason such Grupo VAC
     Limited Offer or decline to accept for any reason such Grupo VAC Limited
     Offer or decline to enter into the purchase agreement related to such Grupo
     VAC Limited Offer or (y) Grupo VAC does not, for any reason, deliver a
     purchase offer related to such Grupo VAC Limited Offer that complies with
     Section 5(g)(vii).

          (iii) Upon receipt of a Grupo VAC ROFO Notice, the Grupo VAC
     Representative shall be entitled to make to Bank of America, the BA
     Investors and Nexus an irrevocable and binding written offer (a "Grupo VAC
     Offer") on behalf of the Grupo VAC Investors to purchase for U.S. dollars
     cash all (but not less than all) of the Shares (or assets, if applicable)
     described in such Grupo VAC ROFO Notice; provided, however, that any such
     Grupo VAC Offer must be delivered to Bank of America, the BA Investors and
     Nexus (A) within 10 (ten) business days after receipt of a Grupo VAC ROFO
     Notice related to any proposed Unsolicited Transfer or (B) within 30
     calendar days after receipt of a Grupo VAC ROFO Notice related to all other
     proposed Transfers (and all other proposed asset sales). To constitute a
     valid Grupo VAC Offer, it shall include a fully executed purchase agreement
     (other than the BA Investors' countersignatures) that (1) only requires
     representations,


                                       26

<PAGE>

     warranties and obligations by the BA Investors (or, if an asset sale, only
     representations, warranties and obligations by the Company) consistent with
     those described in Section 5(f)(ii) of this Agreement and (2) does not
     include any closing conditions other than receipt of required regulatory
     approvals and delivery by the BA Investors of the Shares owned by the BA
     Investors ((or, if an asset sale, delivery of title to the applicable
     assets), free and clear of any liens or encumbrances. Promptly following
     the BA Investors' written acceptance (or, if an asset sale, the Company's
     written acceptance) of a Grupo VAC Offer, the Grupo VAC Investors shall
     consummate such purchase and Transfer as soon as possible, but in no event
     later than 30 (thirty) calendar days (or such longer period as mutually
     agreed to among the Grupo VAC Representative, Nexus and Bank of America)
     after the Grupo VAC Representative's receipt of the BA Investors'
     acceptance (or, if an asset sale, the Company's written acceptance) of such
     Grupo VAC Offer, subject to the receipt of any required regulatory
     approvals.

          (iv) Following (1) the receipt of a Grupo VAC Offer if Bank of
     America, Nexus or the BA Investors (or, if an asset sale, the Company)
     elect not to accept such Grupo VAC Offer or (2) the expiration of the
     periods set forth in Section 5(g)(iii) to make a valid Grupo VAC Offer if
     Grupo VAC does not, for any reason, deliver a purchase offer that complies
     with Section 5(g)(iii), then for a period of (A) 180 days after the date of
     rejection of a Grupo VAC Offer by the BA Investors (or, if an asset sale,
     for a period of 180 days after the date of rejection by the Company of such
     Grupo VAC Offer) or (B) 210 days after the delivery of the Grupo VAC ROFO
     Notice if the Grupo VAC Representative does not deliver a valid Grupo VAC
     Offer (or otherwise fails to comply with Section 5(g)(iii)), the Company
     (to the extent applicable), Nexus, Bank of America and the BA Investors
     (or, with respect to an asset sale, the Company) may, either, at their
     option (x) Transfer the BA Investors' Shares (or, if an asset sale,
     transfer or sell the applicable assets) specified in the Grupo VAC ROFO
     Notice to 1 (one) or more parties at a price and on other economic terms no
     more favorable to such parties (taken together with the pricing as a whole)
     than those offered by the Grupo VAC Representative in the Grupo VAC Offer
     for such Shares (or, if an asset sale, for the applicable assets) or (y)
     enter into a transaction that would otherwise require the prior delivery of
     Grupo VAC RLO Notice.

          (v) If a ROFO-RLO Free Period exists only as the result of the
     delivery of a Grupo VAC RLO Notice in which a valid Grupo VAC Limited Offer
     and purchase agreement were received from the Grupo VAC Representative in
     response to such Grupo VAC RLO Notice (and Section 5(g)(vii) was otherwise
     fully complied with) and such Grupo VAC Limited Offer was rejected or
     otherwise declined by Bank of America, Nexus and the BA Investors, then if
     Nexus or Bank of America desires to enter into a transaction that would
     otherwise require the delivery of a Grupo VAC ROFO Notice under Section
     5(g)(i) (a "Covered Transaction"), at the option of Nexus and Bank of
     America, either (A) notwithstanding the existence of a ROFO-RFL Free
     Period, deliver a Grupo VAC ROFO Notice with respect to such proposed
     Covered Transaction or (B) enter into and consummate such Covered
     Transaction at a per share price and on other economic terms no more
     favorable the acquirer (taken together with the pricing as a whole) than
     those offered by the Grupo VAC Representative in the Grupo VAC Limited
     Offer (it being understood that the foregoing shall in no way require that
     a Covered Transaction include 100% of the outstanding Shares of Maxcom or
     that any Shareholder other than the BA Investors sell their


                                       27

<PAGE>

     Shares). For purposes of clarification, the preceding sentence does not
     modify the requirement that if a Covered Transaction is structured as a
     Drag-Along Sale, the BA Investors' Shares proposed to be included in such
     Drag-Along Sale will be proportional to the percentage of each other
     Shareholder's Shares proposed to be included in such Drag-Along Sale.

          (vi) So long as the Grupo VAC Offer Right Conditions have been
     satisfied, if Nexus, Bank of America or the BA Investors is considering or
     desires to enter into (directly or through the Company) a letter of intent
     (or a binding agreement) with an Independent Third Party regarding a
     potential merger, recapitalization, or reorganization of the Company after
     which (A) at least a majority of the beneficial and record ownership of the
     Shares then outstanding would be owned by such Independent Third Party and
     (B) the BA Investors would continue to own, beneficially or of record,
     Shares (a "Strategic Combination"), then either the Company or Nexus shall
     provide the Grupo VAC Representative with at least 5 (five) business days
     written notice of such intention to enter into such a letter of intent or
     agreement with respect to such potential Strategic Combination ("Grupo VAC
     RLO Notice"). The Grupo VAC RLO Notice shall only be required to disclose
     the fact that Nexus, Bank of America, the BA Investors or the Company may
     enter into a letter of intent or agreement with respect to a Strategic
     Combination and, to the extent known at such time and if the disclosure of
     which is not otherwise contractually restricted, the identity of the
     proposed parties to the Strategic Combination and the estimated pro forma
     equity ownership of the Company after giving effect to such proposed
     Strategic Combination. Other than the disclosure requirements set forth in
     the preceding sentence, the Grupo VAC RLO Notice shall not be required to
     disclose any of the terms of any proposed Strategic Combination.

          (vii) Upon receipt of a Grupo VAC RLO Notice, the Grupo VAC
     Representative shall be entitled to make to Bank of America, the BA
     Investors and Nexus an irrevocable and binding written offer on behalf of
     the Grupo VAC Investors to purchase for U.S. dollars cash all (but not less
     than all) of the Shares then outstanding (a "Grupo VAC Limited Offer").
     Bank of America, Nexus and the BA Investors shall be free to accept or
     reject any Grupo VAC Limited Offer, it being understood that the valuations
     and terms (economic and non-economic) included in any Grupo VAC Limited
     Offer shall not affect or restrict (A) the ability of the Company, Bank of
     America, Nexus and the BA Investors to enter into or consummate any
     Strategic Combination or (B) the terms and conditions of any Strategic
     Combination that may be accepted by the Company, Nexus and/or the BA
     Investors (i.e., the Company, Nexus and the BA Investors may elect to enter
     into a Strategic Combination that is economically inferior to the economic
     terms set forth in a Grupo VAC Limited Offer). If the Grupo VAC
     Representative makes a Grupo VAC Limited Offer acceptable to Nexus, the BA
     Investors and Bank of America, then the Grupo VAC Representative shall
     promptly, and in any event within 5 (five) business days after notice by
     either Nexus or Bank of America that the Grupo VAC Limited Offer's
     valuation and terms are acceptable, deliver a fully executed purchase
     agreement with respect to such Grupo VAC Limited Offer (other than the BA
     Investors' countersignatures) that (1) only requires representations,
     warranties and obligations by the participating Shareholders (or, if an
     asset sale, only representations, warranties and obligations by the
     Company) consistent with those described in Section 5(f)(ii) of this
     Agreement and (2) does not include any closing conditions other than
     receipt of required regulatory approvals and delivery by the Shareholders
     of the Shares, free and


                                       28

<PAGE>

     clear of any liens or encumbrances. Promptly following the BA Investors'
     written acceptance of any such Grupo VAC Limited Offer purchase agreement,
     the Grupo VAC Investors shall consummate such purchase and Transfer as soon
     as possible, but in no event later than 30 (thirty) calendar days (or such
     longer period as mutually agreed to among the Grupo VAC Representative,
     Nexus and Bank of America) after the acceptance of such Grupo VAC Limited
     Offer purchase agreement, subject to the receipt of any required regulatory
     approvals.

          (viii) Following (1) the receipt of a Grupo VAC Limited Offer if the
     BA Investors elect not to accept such Grupo VAC Limited Offer or (2) the
     expiration of the periods set forth in Section 5(g)(vi) to make a valid
     Grupo VAC Limited Offer and deliver a binding purchase agreement contract
     that complies with the requirements set forth in Section 5(g)(vi)) if (A)
     Bank of America, Nexus and the BA Investors decline to accept for any
     reason such Grupo VAC Limited Offer or decline to enter into the purchase
     agreement related to such Grupo VAC Limited Offer or (B) Grupo VAC does
     not, for any reason, deliver a purchase offer related to such Grupo VAC
     Limited Offer that complies with Section 5(g)(vi), then for a period of 210
     days from the date of delivery of the Grupo VAC RLF Notice, the Company,
     Nexus, Bank of America and the BA Investors may, at Nexus's and the BA
     Investors' option, either (x) enter into a letter of intent and/or an
     agreement with respect to a Strategic Combination or (y) subject to Section
     5(g)(v), enter into a transaction that would otherwise require the prior
     delivery of a Grupo VAC ROFO Notice.

          (ix) If, for any reason, the Grupo VAC Representative or any Grupo VAC
     Investor attempts to rescind or otherwise revoke any Grupo VAC Offer or
     Grupo VAC Limited Offer or if the Grupo VAC Investors fail for any reason
     to consummate the purchase of the BA Investors' Shares (or, if an asset
     sale, the purchase of the subject assets) after acceptance of a Grupo VAC
     Offer or Grupo VAC Limited Offer, the Grupo VAC Representatives and the
     Grupo VAC Investors' rights pursuant to this Section 5(g) shall be
     terminated automatically, with respect to such offer and all future offers,
     and without any further action by the Company, Nexus, Bank of America or
     any BA Investor and the Grupo VAC Representative and Grupo VAC Investors
     shall have no further rights thereafter with respect to this Section 5(g).
     For purposes of clarification, an amendment of a Grupo VAC Offer that only
     improves the terms of such Grupo VAC Offer or Grupo VAC Limited Offer for
     the BA Investors (e.g., an increase in the consideration) shall not be
     treated as a revocation of such Grupo VAC Offer or Grupo VAC Limited Offer.

          (x) For purposes of clarification, Nexus and Bank of America may (but
     shall not be required to) deliver a Grupo VAC ROFO Notice and/or Grupo VAC
     RLO Notice at any time, including, without limitation, prior to Nexus, Bank
     of America and/or the Company initiating discussions with any other
     Persons, retaining advisors or soliciting other parties with respect to a
     transaction involving a (1) Transfer of all of the Shares owned
     beneficially or of record by the BA Investors, (2) Drag-Along Sale or (3)
     Sale of the Company, including without limitation, a Strategic Combination;
     provided, however, that any required Grupo VAC ROFO Notice or Grupo VAC RLO
     Notice must still be given within the respective time periods for delivery
     thereof in this Section 5(g).


                                       29

<PAGE>

          (xi) Notwithstanding anything herein to the contrary, any exercise of
     the rights under this Section 5(g) is subject to and conditioned upon the
     Recusal of the Grupo VAC Director (and its alternate), as well as the Grupo
     VAC Representative, Grupo VAC Investors and their respective Affiliates,
     representatives and agents (but, with respect to such representatives and
     agents, only to the extent that such representatives or agents are working
     for or on behalf of any of the Grupo VAC Director (or its alternative), the
     Grupo VAC Representative, any Grupo VAC Investor and/or any of their
     respective Affiliates), from any meeting, telephone conference,
     videoconference, deliberation, analysis, or other discussion by the Board
     or the Company's officers and any vote by Board (or any Committee)
     regarding any of (1) a Sale of the Company (including, without limitation,
     any Strategic Combination), (2) a Drag-Along Sale, (3) a Transfer of all
     the Shares owned beneficially or of record by the BA Investors to any
     Person (or related Persons) other than a Permitted Transferee or other
     Qualified Affiliate of Bank of America, (4) any letter of intent or
     agreement related to such a Sale of the Company, Drag-Along Sale or
     Transfer by the BA Investors, (5) any Grupo VAC Offer, (6) any Grupo VAC
     Limited Offer or (6) any other transaction which would be subject to the
     rights set forth in this Section 5(g) (collectively, the "Restricted
     Matters"). If any Grupo VAC Director (or its alternate), the Grupo VAC
     Representative, any Grupo VAC Investor or any of their respective
     representatives or agents fails to Recuse himself or itself from a
     Restricted Matter, then the Grupo VAC Investors and the Grupo VAC
     Representative shall have no rights under this Section 5(g) with respect to
     such Restricted Matter. For purposes of clarification, the Grupo VAC
     Investors and the Grupo VAC Representative may affirmatively waive (in
     writing) their rights under this Section 5(g) with respect to a specified
     Restricted Matter transaction (as opposed to all Restricted Matters) and in
     such event, the Grupo VAC Investors and the Grupo VAC Representative shall
     have no rights under this Section 5(g) with respect to such Restricted
     Matter transaction and the Recusal requirements of this Section 5(g)(xi)
     would not apply to such Restricted Transaction and the Grupo VAC investors
     and Grupo VAC Director (and its alternate) each shall not be prohibited
     from participating in the discussions related to such Restricted Matter in
     their respective capacities as a Shareholder or a director of the Company.
     "Recusal" means, with respect to a Person, that such Person shall not (A)
     attend or participate in any meeting, telephone conference,
     videoconference, deliberation, analysis, or other discussion by the Board
     or the Company's officers or any vote by the Board (or any Committee)
     regarding any Restricted Matter or (B) receive or review any materials
     (including, without limitation, (x) copies of any agreement (regardless of
     whether in draft or final form), including, without limitation, any letter
     of intent or purchase agreement), any proposal, analysis, opinion,
     memorandum, presentation or summary, (y) any summaries or minutes of any
     meeting of the Company's offices, the Board and/or Committee or (z) any
     written resolutions adopted by the Company's Board or any Committee)
     related to a Restricted Matter. The Recusal requirement set forth in this
     Section 5(g)(xi) shall not prevent the Grupo VAC Representative or any
     Grupo VAC Investor from requesting financial information regarding the
     Company from the Company's officers in connection with the preparation of a
     Grupo VAC Offer or Grupo VAC Limited Offer. Nothing in this Section
     5(g)(xi) shall affect the Grupo VAC Investor's rights to Transfer any
     Shares owned by the Grupo VAC Investors.

     (h) Agreement Regarding Indirect Transfers. Notwithstanding the foregoing,
no Securityholder shall avoid the provisions of this Agreement by (i) making a
Transfer to a Permitted


                                       30

<PAGE>

Transferee and then disposing of or transferring all or any portion of such
Securityholder's interest in any such Permitted Transferee, (ii) transferring
ownership interest of such Securityholder or (iii) by entering into any other
transaction intended to avoid or otherwise circumvent the provisions of this
Section 5. In addition, the provisions of this Section 5(h) shall apply to the
Transfer of any beneficial interests, equity interests or other ownership
interests in (1) any trust (including any Permitted Transferee and successor
thereof) that holds any Shares or Options, assuming for purposes of this Section
5(h) that references to the "Company" herein are references to such trust
(including any Permitted Transferee and successor thereof) and that references
to a "Securityholder" (including for purposes of clarification, optionholder)
are references to the beneficiaries thereof, (2) Nexus-Maxcom Holdings I LLC (so
long as it holds any Shares) assuming for purposes of this Section 5(h) that
references to the "Company" herein are references to Nexus-Maxcom Holdings I,
LLC (including any Permitted Transferee and successor thereof) and that
references to a "Securityholder" are references to the members thereof, and (3)
BASCFC-Maxcom Holdings I LLC (so long as it holds any Shares).

     (i) Permitted Transferees. Notwithstanding anything to the contrary
contained herein, the restrictions set forth in Sections 5(a) through 5(e),
5(g), 5(h) and 5(k) of this Section shall not apply to any Transfer of any
Shares or Options:

          (i) in the case of an individual Securityholder, pursuant to
     applicable laws of descent or among such Securityholder's Family Group;

          (ii) by and among (1) the Securityholders and (2) the Securityholders
     and/or their Qualified Affiliates; provided, however, that if such
     Qualified Affiliate ceases to be a Qualified Affiliate, such Qualified
     Affiliate shall promptly reconvey any such Shares or Options back to the
     transferring Securityholder(s) or optionholder(s), as applicable (or
     otherwise comply with the requirements and obligations set forth in this
     Section 5)); and

          (iii) by and among the BA Investors and/or Bank of America and its
     Qualified Affiliate (the Persons specified in clauses (i) through (iii) of
     this Section 5(i) are collectively referred to herein as "Permitted
     Transferees").

     With respect to any Transfer of Shares or Options to a Permitted
Transferee, the restrictions contained in this Section 5 shall continue to apply
to such Shares and Options held by such Permitted Transferee. For purposes of
clarification, any Transfer by a Qualified Investor to another Qualified
Investor shall be subject to Section 5(l).

     (j) Public Offering Provisions. Nexus and Bank of America each may, at any
time and from time to time, require that the Company take all requisite actions
necessary or advisable in the opinion of Nexus or Bank of America, at the
Company's expense to consummate 1 (one) or more Public Offerings, on terms and
conditions acceptable to Nexus and Bank of America and enable each BA Investor
to freely sell its Shares. At any time following the sixth anniversary of a
Qualified Public Offering and from time to time thereafter, the Grupo VAC
Representative shall have the right to require that the Company take all
requisite actions necessary or advisable in the opinion of the Grupo VAC
Investor, at the Company's expense to consummate 1 (one) or more Public
Offerings, on terms and conditions acceptable to the Grupo VAC Investor and
enable each Investor to freely sell its Shares.


                                       31

<PAGE>

          (i) In connection with any Public Offering requested by Nexus, Bank of
     America or the Grupo VAC Representative, (A) the Company shall be obligated
     to become a public company under the securities laws applicable to such
     Public Offering and take such additional actions as may be requested by
     Nexus and/or Bank of America (or, with respect to any Pubic Offering
     properly requested by the Grupo VAC Representative, such additional actions
     as may be requested by the Grupo VAC Representative) in connection with
     such Public Offering or as required by applicable law to cause the Company
     to become a public company (including entering into underwriting agreements
     in customary form in connection with any registered Public Offering) and
     (B) each of the Securityholders shall cooperate fully with the Company and
     the Company's underwriters and take such additional actions as may be
     requested by Nexus and/or Bank of America in connection with such Public
     Offering (or, with respect to any Pubic Offering properly requested by the
     Grupo VAC Representative, such additional actions as may be requested by
     the Grupo VAC Representative in connection with such Public Offering) or as
     required by applicable law to cause the Company to become a public company.

          (ii) At any time and from time to time, at the request of Nexus or
     Bank of America (each such request, a "Registration Request"), the Company
     shall take all requisite actions at the Company's expense to permit the
     Investors to sell, as soon as practicable, the Shares held by them pursuant
     to a registered Public Offering (which may involve the registration of
     Equity Securities representing an economic ownership interest in such
     Shares) and to enable such holders to freely Transfer their Shares in the
     appropriate market as registered securities under applicable securities
     law, as soon as practicable after such Registration Request. At any time
     following the sixth anniversary of a Qualified Public Offering and from
     time to time thereafter, the Grupo VAC Representative shall have the right
     to deliver a Registration Request on behalf of all of the Investors.

          (iii) In connection with any underwritten Public Offering, Nexus and
     Bank of America shall be entitled to select the investment banker and
     manager of such Public Offering (i.e., the managing underwriter); provided,
     however, that Nexus and Bank of America shall consult with the Grupo VAC
     Representative with respect to the selection of the managing underwriter
     for any Public Offering properly requested by the Grupo VAC Representative.

          (iv) Within 10 (ten) business days after receipt of a Registration
     Request, the Company shall give written notice thereof to each other
     Investor and, shall, subject to the terms set forth in this section and to
     any underwriter cut-backs, include in such registration such number of
     Shares held by the Investors for which the Company has received written
     requests for inclusion within 15 (fifteen) business days after the receipt
     of the Company's notice of such registration.

          (v) The Company shall provide a transfer agent and registrar for the
     Equity Securities registered in a Public Offering. Nexus and Bank of
     America (and, with respect to any Public Offering properly requested by the
     Grupo VAC Representative, the Grupo VAC Representative) shall each have the
     right to request that any such Equity Securities (at the Company's expense)
     be registered at the National Registry of Securities and Intermediaries of
     the National Banking and Securities Commission of Mexico. In connection
     with any


                                       32

<PAGE>

     registration and Public Offering, the Company and the holders of Equity
     Securities shall use their respective reasonable best efforts to cause the
     Company to effect the registration of any such registered Equity Securities
     and shall take all such actions to enable the Investors to sell their
     Equity Securities in a public sale, or otherwise freely Transfer their
     Equity Securities without restrictions (other than any such restrictions
     required by the underwriters of all holders of Equity Securities
     participating in such offering), in accordance with the Mexican securities
     laws and/or, to the extent applicable, United States federal and state
     securities laws and others. The Company for this purpose shall assist each
     Investor in connection with such public sale and shall furnish all
     information which Nexus, Bank of America, such Investor or the managing
     underwriters deem necessary or desirable to be disclosed in any prospectus
     to be distributed in connection with such public sale. Each Investor shall
     be entitled to participate in each Public Offering on a pro rata basis
     (based on the aggregate Equity Securities requested by all Investors to be
     included in such Public Offering), subject to any cut-backs required by the
     underwriters in any underwritten offering. In addition, in connection with
     any secondary offering of the Equity Securities, the Investors will be
     entitled to participate in such secondary offering prior to any other
     Securityholder. If a primary or secondary offering is an underwritten
     offering and if the Board, Nexus and Bank of America reasonably determine,
     based upon the written advice of the managing underwriter(s), that the
     number of Equity Securities requested to be included in such offering
     exceeds the number of such securities which can be sold therein without
     adversely affecting the marketability of the offering, the Company will
     include in such registration (A) the number and type of Equity Securities
     requested by the Investors to be included which in the opinion of such
     underwriters, can be sold pro rata among the Investors without adverse
     effect on the basis of the number of Equity Securities to be registered
     held by each such Investor and (B) other Equity Securities requested to be
     included in such registration, pro rata among the holders of such Equity
     Securities on the basis of the number of Equity Securities held by each
     such Securityholder. Notwithstanding anything herein to the contrary, until
     the earlier of (i) such time as the BA Investors beneficially own less than
     five percent (5%) of the then outstanding Shares or (ii) the sixth
     anniversary of a Qualified Public Offering, the Grupo VAC Investors shall
     only be entitled to participate in an underwritten offering (or similar
     registration) of Shares after the inclusion in any such underwritten
     offering (or similar registration) of all of the Shares owned by the other
     Investors that are requested to be so included by the other Investors in
     such underwritten offering (or similar registration) of Shares.

          (vi) If so requested by the underwriters managing any such offering,
     (A) no holder of Equity Securities shall, directly or indirectly, Transfer
     or offer or agree to Transfer (other than to Affiliates and/or
     equityholders of such holders who agree to be similarly bound) any such
     Equity Securities during the 30 (thirty) days prior to and the 180-day
     period beginning on the expected effective date of any registered Public
     Offering (other than with respect to any securities actually being sold in
     such Public Offering); provided, however, that following a Qualified Public
     Offering the lock-up period for any subsequent Public Offering shall be the
     30 (thirty) days prior to and the 90-day period beginning on the expected
     effective date of any registered Public Offering and (B) each holder of
     Equity Securities shall, if requested by the Company, execute a lock-up
     agreement consistent with the terms of the preceding clause (A), subject to
     the approval by Nexus or Bank of America of the terms of such lock-up
     agreement. In each case, the Company shall use its commercially reasonable


                                       33

<PAGE>

     efforts to notify all record Securityholders of the exact date of any
     lock-up period to which such holders are subject. Any attempted Transfer of
     Equity Securities in violation of these provisions shall be null and void
     ab initio and shall not be consented to or recognized or registered by the
     Company for any purpose.

          (vii) At the request of Nexus at any time following a Qualified Public
     Offering (or the Grupo VAC Representative at any time following the sixth
     anniversary of a Qualified Public Offering), the Company shall use its best
     efforts to file with the Securities and Exchange Commission a shelf
     registration statement pursuant to Rule 415 promulgated under the
     Securities Act.

          (viii) Following a Public Offering, upon the reasonable request of any
     Securityholder, the Company shall, at its expense, provide such
     Securityholder a reasonable number of copies of the registration statement
     and prospectus relating to the registered Equity Securities of the Company.

          (ix) The Company will provide reasonable and customary indemnification
     to each participating Securityholder (including such participant's
     directors, officers and employees) in a registered Public Offering, for
     losses caused by any material misstatement or omission in any registration
     statement or prospectus provided by the Company to such participating
     Securityholder for use in connection with a resale of Shares, except
     insofar as such losses are caused by a material misstatement or omission
     based upon information relating to information furnished to the Company by
     any of the participating Securityholders. As a condition to participating
     in any registered Public Offering, each participating Securityholder will
     provide reasonable and customary indemnification (in form and substance
     satisfactory to Nexus) to the Company and its directors, officers, and
     affiliates but only with reference to information relating to such
     participating Securityholder furnished to the Company by or on behalf of
     such participant expressly for use in any registration statement or
     prospectus.

     (k) Shares held by CPO Trustee. Any Shares held of record by the CPO
Trustee may not be directly Transferred by the CPO Trustee without the consent
of the Board (including at least 1 (one) Nexus Director); provided, however,
that nothing in this Section 5 shall restrict the Transfer of any CPOs in
accordance with the Trust Agreement.

     (l) Participation Right (Tag-Along Rights) on Transfers by Qualified
Investors to other Qualified Investors.

          (i) In connection with any Transfer by a Qualified Investor to a
     Permitted Transferee, if such Transfer is to a Permitted Transferee that is
     a Qualified Investor that is not a Qualified Affiliate of the transferring
     Qualified Investor (and other than a Transfer pursuant to a Drag-Along Sale
     or a Transfer to the Grupo VAC Investors pursuant to Section 5(g)), then
     (A) the other Qualified Investors shall have the right to participate in
     such Transfer pursuant to this Section 5(l), (B) such transferring
     Qualified Investor shall deliver written notice thereof (the "Special
     Tag-Along Right Notice") to the Secretary of the Board, and (C) the
     Secretary of the Board shall then promptly (but in any event within 5
     (five) days) deliver to the other Qualified Investors, at the registered
     addresses of such Qualified Investor on file with the Company, such Special
     Tag-Along Right Notice, disclosing the number of Shares to be Transferred,
     the proposed price, terms and conditions of the Transfer (including,


                                       34

<PAGE>

     without limitation, a description of any expense, escrow, holdback,
     earn-out, indemnity or similar obligations to which the participating
     Securityholders shall be responsible) and the identity of the prospective
     transferee(s).

          (ii) All Qualified Investors may elect to participate on a pro rata
     basis (based on the number of Shares) in the contemplated Transfer
     described in the Special Tag-Along Right Notice by giving written notice to
     the transferring Qualified Investor within 20 (twenty) days after delivery
     of the Special Tag-Along Right Notice to the Company (the "Special
     Tag-Along Window"). Each such Qualified Investor may participate in the
     contemplated Transfer at the same price and, subject to clause (vi) below,
     on the same terms specified in the Special Tag-Along Right Notice;
     provided, however, that if a Qualified Investor holds more than 1 (one)
     class or series of Shares, such Qualified Investor's rights under this
     Section 5(l) to participate in such Transfer shall be allocated
     proportionately among all of the Shares owned by such Qualified Investor
     (e.g. if a Transfer pursuant to a Special Tag-Along-Right Notice is
     contemplated, a Qualified Investor holding 1,000 Series B Shares and 1,000
     Series N Shares would be required to Transfer an equal number of both
     Series B and Series N Shares). The failure to deliver notice electing to
     participate within a Special Tag-Along Window shall be deemed an automatic
     and complete waiver of all rights to participate in such Transfer pursuant
     to this Section 5(l).

          (iii) If no Qualified Investor elects to participate in the
     contemplated Transfer (either by giving notice to such effect or failing to
     give notice within the Special Tag-Along Window), then, pursuant to and on
     the terms substantially as described in the Special Tag-Along Right Notice,
     the transferring Qualified Investor may Transfer such Shares to the other
     Qualified Investor(s) specified in the Special Tag-Along Right Notice for a
     period equal to 120 days after the expiration of the Special Tag-Along
     Window; provided, however, that there will be an automatic 60-day extension
     of such 120-day period to the extent that regulatory approvals for a
     Transfer have not been obtained within such original 120-day period. If the
     transferring Qualified Investor fails to Transfer such Shares to such other
     Qualified Investor as described in the Special Tag-Along Notice within such
     applicable period, the transferring Qualified Investor shall not Transfer
     such Shares to such Qualified Investor without again complying with the
     provisions of this Section 5(l).

          (iv) No transferring Qualified Investor shall Transfer any of its
     Shares to another Qualified Investor that is not a Qualified Affiliate of
     the transferring Qualified Investor if such prospective transferee declines
     to allow the participation of the other Qualified Investors on the terms
     provided in this Section 5(l), unless and only to the extent that the
     prospective transferee may not hold such other Qualified Investors' Shares
     because of ownership restrictions on such Shares imposed by the Company
     Bylaws or applicable Mexican law.

          (v) The right of each Qualified Investor to participate in a Transfer
     pursuant to this Section 5(l) is subject to such Qualified Investor's
     satisfaction of the same conditions set forth in Section 5(e)(v) for
     participation in a Transfer under Section 5(e) (i.e., the same limitations
     on the representations and warranties, indemnification obligations,
     execution of ancillary documents, etc. will apply to the participating
     Qualified Investors).


                                       35

<PAGE>

          (vi) To the extent that a Qualified Investor holds Shares subject to
     restrictions on ownership pursuant to the Company Bylaws or applicable
     Mexican law (e.g., Series A Shares may only be owned by Mexicans), such
     Qualified Investor will only be eligible to Transfer such restricted Shares
     pursuant to this Section 5(l) to purchasers who are eligible to own such
     restricted Shares.

     (m) Restriction on Competition by Grupo VAC Investors. As a condition to
the Grupo VAC Investors' rights under Section 3, Section 2(a), and Section 4(a),
during the five-year period beginning on the Closing Date (as defined in the TR
Purchase Agreement), the Grupo VAC Investors will not and shall cause each of
their Affiliates not to, directly or indirectly, (A) participate in any business
that is competitive with the telecommunications businesses conducted or proposed
to be conducted in Mexico or the United States as of the Closing Date by the
Company, any of its subsidiaries or any TR Company (as defined in the TR
Purchase Agreement), including, without limitation, using all or any portion of
the Two FO Strands (as defined in the TR Purchase Agreement) in a manner that
directly or indirectly competes with the Company's telecommunications business
(including, without limitation, leasing or otherwise commercializing the Two FO
Strands) or (B) own any interest in, operate, manage, join, control, finance,
participate in the ownership, management, operation or control of, or be paid or
employed by, or acquire any securities of, or otherwise become associated with
or provide assistance to, as an employee, consultant, director, officer,
shareholder, partner, member, agent, associate, principal, creditor,
representative or in any other capacity, any sole proprietorship or business
entity engaged either directly or indirectly in competition with the
telecommunications businesses conducted or proposed to be conducted by Company
or the TR Companies as of the Closing Date; provided, however, that the
foregoing shall not prohibit or restrict the ability of the Grupo VAC Investors
and their respective Affiliates to collectively own, beneficially or of record,
less than five percent (5%) of any publicly-traded corporation. The Grupo VAC
Investors understand and acknowledge that their rights under Section 3, Section
2(a), and Section 4(a) shall be automatically terminated upon any violation of
this Section 5(m).

     (n) Termination.

          (i) The restrictions on Transfer contained in Section 5(b) shall
     terminate upon the earliest to occur of (A) the consummation of a Sale of
     the Company, (B) the consummation of a Qualified Public Offering in which
     all the Shares owned beneficially by the BA Investors are registered and
     sold, (C) subject to the prior written consent thereto of Nexus, upon the
     requirement of the managing underwriter in connection with a Qualified
     Public Offering, (D) the effectiveness of the Regulatory Amendments and the
     modifications to the Company's capital structure described in Section 6,
     and (E) upon the agreement of the Board and Nexus to so terminate.

          (ii) The right of first refusal set forth in Section 5(c) shall
     terminate upon the earliest to occur of (A) the consummation of a Sale of
     the Company, (B) the effectiveness of the Regulatory Amendments and the
     modifications to the Company's capital structure described in Section 6,
     and (C) upon the agreement of the Board and Nexus to so terminate such
     restrictions.


                                       36

<PAGE>

          (iii) The requirements contained in Sections 5(d), 5(e), 5(f), 5(g)
     and 5(l) shall terminate upon the earliest to occur of (A) the consummation
     of a Sale of the Company, (B) the consummation of a Qualified Public
     Offering in which all the Shares owned beneficially by the BA Investors are
     registered and sold; provided, however, that in the case of any termination
     of the requirements contained in Section 5(d), 5(e) or 5(l) pursuant to
     this clause (B), that the Grupo VAC Investors also agree to such
     termination, (C) subject to the prior consent thereto of Nexus, upon the
     written requirement of the managing underwriter in connection with a
     Qualified Public Offering, and (D) upon the agreement of the Board, Nexus
     and the Grupo VAC Representative to so terminate all or any of the
     requirements in such sections of this Agreement.

          (iv) The restrictions on Transfer contained in Section 5(k) shall
     terminate upon the earlier to occur of (A) the consummation of a Sale of
     the Company and (B) the dissolution of the trust established pursuant to
     the CPO Investment Trust Agreement; provided, however, that the
     restrictions on Transfer set forth in this Section 5 shall continue to
     apply to the Shares previously held by the CPO Trustee.

          (v) The restrictions contained in Section 5(m) shall terminate upon
     the earlier to occur of (A) the fifth anniversary of the Closing Date and
     (B) the agreement of the Board and Nexus to so terminate such restrictions.

     SECTION 6. FOREIGN INVESTMENT AND TELECOMMUNICATION LAW. If at any time the
Foreign Investment Law and the Federal Telecommunications Law of Mexico are
amended so as to permit the unrestricted ownership and/or control of the Company
by 1 (one) or more foreign (i.e., non-Mexican) entities, upon the effectiveness
of such amendments (the "Regulatory Amendments") the Shares shall be
automatically converted on a one-to-one basis into a single series of common
shares with voting rights determined on a pro rata basis based on all such
common shares voting together as a single class. The Company and each
Securityholder shall take all actions necessary or requested by Nexus or Bank of
America in connection with effectuating the modifications to the Company's
capital structure described in this Section 6.

     SECTION 7. SHARE CERTIFICATE NOTATION.

     (a) The Company's share certificates for all of its shares (other than
certificates representing Series N Shares held by the CPO Trustee) shall bear
the following legend and any other legend required by the Board and any Nexus
Director:

          "The shares represented by this certificate are subject to the
          restrictions specified herein and in the Third Amended and Restated
          Securityholders Agreement, dated as of July 19, 2006, as amended and
          modified from time to time, a copy of which is on file at the
          Company's offices."

     (b) The Company shall place the legend described in subsection (a) above on
each and every certificate evidencing Shares (other than certificates
representing Series N Shares held by the CPO Trustee) outstanding as of the date
hereof, including any certificate evidencing Shares that was


                                       37

<PAGE>

issued prior to the date hereof. The legend set forth above in subsection (a)
shall be removed from the certificates evidencing any Shares upon their Transfer
in a Public Sale.

     (c) The Company shall register this Agreement (and any amendments hereto)
in its head office, shall enter into the Securityholders' Registry Book a
notation acceptable to the Board and at least one Nexus Director, shall certify
to the Securityholders that such notation has been made to the Securityholders'
Registry Book and shall comply fully with the obligations undertaken herein.

     SECTION 8. MISCELLANEOUS.

     (a) Amendment and Waiver. Except as otherwise expressly provided herein, no
modification, amendment or waiver of any provision of this Agreement shall be
effective against the Company or the Securityholders unless such modification,
amendment or waiver is approved in writing by each of (i) the Company and (ii)
Nexus; provided, however, that in the event that any such modification,
amendment or waiver would materially and adversely affect the rights or
obligations of a holder or group of holders of Shares in a manner different than
any other holders of Shares, then such modification, amendment or waiver will
require the consent of such holder of Shares or a majority of the Shares held by
such group of holders materially and adversely affected; provided, further, that
in the event that any such modification, amendment or waiver would materially
and adversely affect the rights or obligations of the Grupo VAC Investors. Such
modification, amendment or waiver will require the consent of the Grupo VAC
Representative.

     (b) Successors and Assigns. Subject to the restrictions on Transfer set
forth in Section 5, this Agreement and each of the rights and obligations
hereunder shall bind and inure to the benefit of and be enforceable by the
Securityholders and any subsequent holders of Securities and their respective
successors and assigns, and shall be binding upon the Company and it successors
and assigns. In addition, whether or not any express assignment has been made,
unless otherwise expressly provided herein, the provisions of this Agreement
which are for any Securityholder's benefit as a holder of Securities are also
for the benefit of, and enforceable by, any subsequent holder of such
Securities; provided, however, that such subsequent holder has acquired such
Securities in accordance with the provisions of this Agreement, including
Section 5 above.

     (c) Counterparts. This Agreement may be executed in multiple counterparts
(including by means of telecopied signature pages), each of which shall be an
original and all of which taken together shall constitute one and the same
agreement.

     (d) Notices. Any notice provided for in this Agreement shall be in writing
and shall be either personally delivered, sent by reputable overnight courier
service (charges prepaid) or sent by facsimile and followed with a copy sent by
a reputable overnight courier (charges prepaid) to the Company and any other
recipient at the address indicated on the signature pages hereto and to any
subsequent holder of Shares subject to this Agreement at such address as
indicated by the Company's records, or at such address or to the attention of
such other Person as the recipient party has specified by prior written notice
to the sending party. Notices shall be deemed to have been given hereunder (i)
upon receipt by or delivery to the recipient party, (ii) upon personal delivery
as set forth above, or (iii) the date delivery is confirmed by facsimile or
reputable overnight courier as set forth above; provided, however, that any
service of process or other notice of any court or other legal proceeding or
action shall be made by personal delivery to the recipient or its agent for
service of process


                                       38

<PAGE>

(including the Process Agent (as defined below) and any of its employees). Each
notice delivered under this Agreement shall be made in English and the English
version shall govern in the event of any inconsistency with any non-English
translation thereof.

     (e) Governing Law; Jurisdiction. UNLESS AND EXCEPT TO THE EXTENT ANY
PROVISION HEREOF IS REQUIRED BY MEXICAN LAW TO BE GOVERNED BY MEXICAN LAW, THIS
AGREEMENT, ITS INTERPRETATION AND ENFORCEABILITY AND THE RIGHTS AND OBLIGATIONS
OF THE PARTIES HEREUNDER SHALL BE CONSTRUED IN ACCORDANCE WITH AND BE GOVERNED
BY THE INTERNAL LAWS (AND NOT THE LAWS OF CONFLICT) OF THE STATE OF ILLINOIS,
UNITED STATES OF AMERICA. Any legal action or proceeding to enforce the
obligation of any party to resolve any dispute in accordance with Section 8(f)
or to enforce an order or award made pursuant to an arbitration under Section
8(f) may be brought in (i) the courts of the State of Illinois, United States of
America, (ii) the courts of the United States for the Northern District of
Illinois, (iii) the competent courts of Mexico, D.F., pursuant to the New York
Convention for the Recognition and Enforcement of Foreign Arbitration Awards, or
(iv) any other court of competent jurisdiction and, by execution and delivery of
this Agreement, each party hereby irrevocably accepts for itself and in respect
of its property, generally and unconditionally, the jurisdiction of each of the
aforesaid courts. The Company, each Existing Securityholders and each Additional
Securityholders not resident in or organized under the laws of the United States
each hereby irrevocably appoints CT Corporation (the "Process Agent") (a process
agent service company located in the United States at 208 S. LaSalle Street,
Chicago, Illinois, 60604), as its authorized agent for service of process in any
such court and notice under this Agreement and agrees to maintain such
appointment for so long as any Investor owns any Securities and to further
evidence such appointment in an escritura publica executed before a notary
public in Mexico in conformity with Article 2596 of the Civil Code of the
Federal District and the 1958 Protocol on the Uniformity of Powers of Attorney
to be Utilized Abroad. The Company shall pay all expenses in connection with
such appointment of CT Corporation as the Company's and such Existing
Securityholder's and Additional Securityholder's agent. Each party hereby
further irrevocably waives any claim that any such courts lack jurisdiction over
such party or that service of process or venue is improper, and agrees not to
plead or claim, in any legal action or proceeding with respect to this Agreement
brought in any of the aforesaid courts, that any such court lacks jurisdiction
over such party or that venue or service of process is improper or that the
action has been brought in an inconvenient forum. Nothing herein shall affect
the right of any Investor to serve process in any other manner permitted by law.

     (f) Arbitration. If any dispute or claim arises out of this Agreement, or
as to the rights and liabilities of the parties hereunder, or as to the breach
or invalidity hereof, or in connection with the construction of this Agreement,
including any dispute, claim or difference as to whether an issue can be
arbitrated, the parties shall settle such dispute exclusively by binding
arbitration by an arbitrator appointed by the International Chamber of Commerce
in accordance with the rules of the International Chamber of Commerce in New
York City in effect as of the date of commencement of the arbitration. The
arbitration shall be commenced by the delivery of written notice by the party
seeking arbitration to the other parties to the dispute, shall be held in New
York City, New York, unless the parties mutually agree to have the arbitration
held elsewhere, shall be conducted solely in the English language, shall utilize
the English versions of all of the Transaction Agreements, the Company Bylaws,
and this Agreement and judgment upon the award made therein may be entered by
any court having jurisdiction there over; provided, however, that nothing


                                       39

<PAGE>

contained in this Section 8(f) shall be construed to limit or preclude a party
from bringing any action in any court of competent jurisdiction in the United
States or Mexico solely for the purpose of enforcing any final judgment or award
made pursuant to an arbitration under this Section 8(f) or enforcing the
obligation of any other party hereto to resolve any dispute in accordance with
this Section 8(f). Notwithstanding anything to the contrary in this Agreement,
the unsuccessful party in any such arbitration proceeding shall pay to the
successful parties all costs and expenses incurred by the successful party in
connection with such arbitration proceeding, including all costs and expenses of
outside counsel and all reasonable costs and expenses of their advisers.

     (g) Governing Language. This Agreement has been negotiated and executed by
the parties hereto in English. A Spanish translation of this Agreement has been
prepared solely for convenience. As among the Company and the Securityholders,
in the event of any inconsistency between or among the non-English and the
English versions of this Agreement and any other Transaction Agreement or this
Agreement, the provisions of the English version shall prevail.

     (h) U.S. GAAP. Any calculations and accounting determinations under this
Agreement, shall be made in accordance with United States generally accepted
accounting principles, consistently applied in the preparation of the Company's
audited financial statements.

     (i) Rule of Construction. Each of the parties hereto acknowledge and agree
that such party and its counsel have reviewed and revised this Agreement and
that the normal rule of construction to the effect that any ambiguities are to
be resolved against the drafting party shall not be employed in the
interpretation of this Agreement or any amendment, exhibit or schedule hereto.

     (j) Further Assurances. Each beneficial owner of Shares shall cause the
record owner of such Shares to comply fully with each and every obligation
imposed on the holder of such Shares under this Agreement. Each of the parties
hereto agrees to take such additional actions, including executing and
delivering, or causing to be executed and delivered, to the Company such
instruments as Nexus or the Company may from time to time reasonably request or
as may be otherwise necessary to more effectively effectuate the corporate
governance matters and restrictions on Transfer set forth herein.

     (k) Complete Agreement. This Agreement, the Security Trust Agreement the
other Transaction Agreements and the other documents and writings expressly
referred to herein or therein or delivered pursuant hereto or thereto (in their
English versions) contain the entire understanding of the parties hereto with
respect to the subject matter hereof and thereof and supersede all prior
agreements, representations and understandings, whether written and oral, among
any of the parties with respect to the subject matter hereof and thereof
(including without limitation, the First and Second Amended and Restated
Securityholders Agreements).

     (l) Special Provisions for Optionholders.

          (i) Director and Management Options. The Management Option Plan (as
     defined in that certain agreement, dated as of May 8, 1998 among certain
     investors, the Company and certain of the Existing Securityholders, as
     amended and modified from time to time in accordance with its terms), the
     New Stock Option Plan 2001-2003 (as adopted by the Board on February 19,
     2002 and approved by the Company's shareholders on March 5, 2002), and the
     Fulvio Del Valle Stock Option Plan (as adopted by the Board on February 19,


                                       40

<PAGE>

     2002 and approved by the Company's shareholders on March 5, 2002) each
     grants options ("Management Options") to members of the Company's
     management, members of the Board and to certain management service
     providers for the acquisition of Series N Shares (shares acquired pursuant
     to the Management Options or as a result of a non-prohibited assignment or
     Transfer thereof being referred to herein as "Management Shares") as set
     forth therein. Certain options granted under the Management Option Plan for
     management services in 2000 to BAICC, LA Strategic Capital Partners II and
     B&A have been renegotiated by the Company and such optionholders
     (collectively, the "2000 Special Options"). The revised terms of the 2000
     Special Options were approved by the Board on February 19, 2002 and the
     Company's shareholders on March 5, 2002. Subject to the execution by each
     party exercising any Management Option (including any 2000 Special
     Options), to the extent such party is not already a party hereto, of a
     counterpart signature page to this Agreement which binds it to the
     provisions of this Agreement, the parties hereto hereby agree that such
     Management Options, including the 2000 Special Options may be exercised
     from time to time and the Management Shares may be issued upon each such
     exercise, in each case subject to the terms of the Management Option Plan,
     without any further action or approval by any of the Securityholders or the
     Board and that each recipient of a Management Option, upon the exercise of
     any such Management Option, shall for all purposes of this Agreement be
     deemed to be an "Existing Securityholders," and a "Securityholder" with
     respect to such Management Shares.

          (ii) Amsterdam Options. The Engagement Letter dated November 13, 1997
     as amended on March 13, 1998 and April 2, 1998 between the Company and
     Amsterdam Pacific LLC grants options ("Amsterdam Options") to Amsterdam
     Pacific LLC (together with any other holder of any Amsterdam Options,
     "APLLC") for the acquisition of Series N Shares (shares acquired pursuant
     to the Amsterdam Options or as a result of a non-prohibited assignment or
     Transfer thereof being referred to herein as "Amsterdam Shares") as set
     forth therein. Subject to the execution by APLLC of a counterpart signature
     page to this Agreement which binds it to the provisions of this Agreement,
     the parties hereto hereby agree that the Amsterdam Options may be exercised
     from time to time and the Amsterdam Shares may be issued upon each such
     exercise in each case subject to the terms of the Engagement Letter,
     without any further action or approval by any of the Securityholders or the
     Board and that APLLC, upon the exercise of any Amsterdam Options, shall for
     all purposes of this Agreement be deemed to be an "Additional
     Securityholders," and a "Securityholder."

     (m) Termination of Agreement. Notwithstanding anything to the contrary
contained in this Agreement, at such time as the Investors collectively hold,
directly or indirectly, less than ten percent (10%) of the then outstanding
Shares, this Agreement shall automatically terminate and be of no further force
or effect.

     (n) Understanding Among the Securityholders. The determination of each
Securityholder to acquire Shares and enter into this Agreement has been made by
such Securityholder independent of any other Securityholder and independent of
any statements or opinions as to the advisability of such purchase or as to the
properties, business, prospects or condition (financial or otherwise) of the
Company and its subsidiaries which may have been made or given to such
Securityholder by any other Securityholder or by any agent or employee of any
other


                                       41

<PAGE>

Securityholder. Each Securityholder acknowledges and agrees that no other
Securityholder shall be responsible in any way or held liable or accountable to
any extent for any information, documents, materials, analysis, projections,
plans or other data (or compilations thereof) relating to the Company or the
transactions contemplated hereby (collectively, "Investment Data") provided to
such Securityholder by any other Securityholder, and each Securityholder agrees
to hold harmless and not make any claims against any other Securityholder with
respect to any Investment Data provided to such Securityholder by such other
Securityholder. In addition, it is acknowledged by each of the other
Securityholder that none of the BA Investors has acted as an agent of such
Securityholder in connection with the making of its investment in the Shares and
that none of Nexus, BASCFC, BankAmerica International Investment Corporation or
LA Strategic Partners II is or shall be acting as an agent of such
Securityholder in connection with monitoring its investment hereunder.

     (o) Acknowledgment re Kirkland & Ellis LLP. Maxcom, Nexus, BASCFC,
Bankamerica International Investment Corporation and certain other of the BA
Investors have retained Kirkland & Ellis LLP in connection with this Agreement
and may in the future retain Kirkland & Ellis LLP in connection with the matters
contemplated by this Agreement. Each of the other Securityholder understands
that Kirkland & Ellis LLP is not representing and shall not be deemed to be
representing any of such other Securityholder in connection with this Agreement
or other matters contemplated by this Agreement unless and until (i)
specifically requested by such other Securityholder and agreed to by Kirkland &
Ellis LLP, and (ii) such other Securityholder signs a written retention and
conflict waiver letter provided by Kirkland & Ellis LLP.

                                     *****


                                       42
<PAGE>

          IN WITNESS WHEREOF, the parties hereto have executed this Third
Amended and Restated Securityholders agreement on the day and year first above
written(1).

                                        COMPANY:

                                        MAXCOM TELECOMUNICACIONES, S.A. de C.V.


                                        By:
                                            ------------------------------------
                                        Name:
                                              ----------------------------------
                                        Its:
                                             -----------------------------------

                                        Address:
                                        C. Guillermo Gonzalez Camarena No. 2000
                                        Penthouse
                                        Col. Centro de Ciudad Santa Fe
                                        C.P. 01210 Mexico, D.F.
                                        Telecopy: 52-55-5147-8655
                                        Attention: Chief Executive Officer
                                        With a copy to: General Counsel

                                        With an additional copy to:

                                        Nexus-Banc of America Fund II, L.P.
                                        c/o Nexus Partners LLC
                                        400 Skokie Boulevard - Suite 265
                                        Northbrook, Illinois 60062, U.S.A.
                                        Telecopy: (847) 480-4409
                                        Attention: Jacques Gliksberg

----------
(1)  GONZALO ALARCON TO UPDATE SIGNATURE PAGES

     SIGNATURE PAGE TO THIRD AMENDED AND RESTATED SECURITYHOLDERS AGREEMENT

<PAGE>

                                        ORIGINAL INVESTORS:

                                        BANKAMERICA INTERNATIONAL
                                        INVESTMENT CORPORATION


                                        By:
                                            ------------------------------------
                                        Name: Jacques Gliksberg
                                        Its: Authorized Signatory

                                        Address:
                                        c/o Nexus Partners LLC
                                        400 Skokie Boulevard - Suite 265
                                        Northbrook, IL 60062
                                        Telecopy: (847) 480-4409
                                        Attention: Jacques Gliksberg


                                        BANKAMERICA INVESTMENT CORPORATION


                                        By:
                                            ------------------------------------
                                        Name: Jacques Gliksberg
                                        Its: Authorized Signatory

                                        Address:
                                        c/o Nexus Partners LLC
                                        400 Skokie Boulevard - Suite 265
                                        Northbrook, IL 60062
                                        Telecopy: (847) 480-4409
                                        Attention: Jacques Gliksberg


                                        ----------------------------------------
                                        Edward McCaffrey, as a "BAIIC Investor"

                                        Address:
                                        c/o Nexus Partners LLC
                                        400 Skokie Boulevard - Suite 265
                                        Northbrook, IL 60062
                                        Telecopy: (847) 4804409

     SIGNATURE PAGE TO THIRD AMENDED AND RESTATED SECURITYHOLDERS AGREEMENT

<PAGE>

                                        BACHOW INVESTMENT PARTNERS III, LP

                                        By: Bala Equity Partners, L.P.
                                        Its: General Partner

                                        By: Bala Equity, Inc.
                                        Its: General Partner


                                        By:
                                            ------------------------------------
                                        Name:
                                              ----------------------------------
                                        Its:
                                             -----------------------------------

                                        Address:
                                        3 Bala Plaza East Suite 502
                                        Bala Cynwyd, Pennsylvania 19004, U.S.A.
                                        Telecopy: (610) 660-4930
                                        Attention: Salvatore A. Grasso


                                        ----------------------------------------
                                        Paul S. Bachow, as a "Bachow Investor"
                                        Address:
                                        3 Bala Plaza East, Suite 502
                                        Bala Cynwyd, Pennsylvania 19004, U.S.A.
                                        Telecopy: (610) 660-4930


                                        ----------------------------------------
                                        Salvatore A. Grasso, as a "Bachow
                                        Investor"

                                        Address:
                                        3 Bala Plaza East, Suite 502
                                        Bala Cynwyd, Pennsylvania 19004, U.S.A.
                                        Telecopy: (610) 660-4930


                                        ----------------------------------------
                                        Jay D. Seid, as a "Bachow Investor"

                                        Address:
                                        3 Bala Plaza East, Suite 502
                                        Bala Cynwyd, Pennsylvania 19004, U.S.A.
                                        Telecopy: (610) 660-4930

     SIGNATURE PAGE TO THIRD AMENDED AND RESTATED SECURITYHOLDERS AGREEMENT

<PAGE>

                                        LATINVEST STRATEGIC INVESTMENT FUND,
                                        L.P.


                                        By:
                                            ------------------------------------
                                        Name:
                                              ----------------------------------
                                        Its:
                                             -----------------------------------

                                        Address:
                                        6000 Est. Charlotte Amalie, Suite 4
                                        St. Thomas 00802, U.S. Virgin Islands
                                        Telecopy: 340-777-3880
                                        Attention: Hurdle H. (Trip) Lee, III

     SIGNATURE PAGE TO THIRD AMENDED AND RESTATED SECURITYHOLDERS AGREEMENT

<PAGE>

                                        BAS CAPITAL FUNDING CORPORATION


                                        By:
                                            ------------------------------------
                                        Name:
                                              ----------------------------------
                                        Its:
                                             -----------------------------------

                                        Address:
                                        c/o Nexus Partners LLC
                                        400 Skokie Boulevard - Suite 265
                                        Northbrook, IL 60062
                                        Telecopy: (847) 480-4409
                                        Attention: Jacques Gliksberg


                                        BASCFC-MAXCOM HOLDINGS I, LLC


                                        By:
                                            ------------------------------------
                                        Name: Jacques Gliksberg
                                        Its: Manager

                                        Address:
                                        c/o BAS Capital Funding Corporation
                                        c/o Nexus Partners LLC
                                        400 Skokie Boulevard - Suite 265
                                        Northbrook, IL 60062
                                        Telecopy: (847) 480-4409
                                        Attention:  Jacques Gliksberg

     SIGNATURE PAGE TO THIRD AMENDED AND RESTATED SECURITYHOLDERS AGREEMENT

<PAGE>

                                        NEXUS-MAXCOM HOLDINGS I, LLC


                                        By:
                                            ------------------------------------
                                        Name: Jacques Gliksberg
                                        Its:  Manager

                                        Address:
                                        c/o Nexus Partners LLC
                                        400 Skokie Boulevard - Suite 265
                                        Northbrook, IL 60062
                                        Telecopy: (847) 480-4409
                                        Attention: Jacques Gliksberg


                                        NEXUS-BANC OF AMERICA FUND II, L.P.,

                                        By: Nexus Partners II, L.P.
                                        Its: General Partner

                                        By: Nexus Partners, LLC
                                        Its: General Partner


                                        By:
                                            ------------------------------------
                                        Name: Jacques Gliksberg
                                        Its: Manager

                                        Address:
                                        c/o Nexus Partners LLC
                                        400 Skokie Boulevard - Suite 265
                                        Northbrook, IL 60062
                                        Telecopy: (847) 480-4409
                                        Attention: Jacques Gliksberg

     SIGNATURE PAGE TO THIRD AMENDED AND RESTATED SECURITYHOLDERS AGREEMENT

<PAGE>

                                        CREDIT SUISSE FIRST BOSTON CORPORATION


                                        By:
                                            ------------------------------------
                                        Name:
                                              ----------------------------------
                                        Its:
                                             -----------------------------------

                                        Address: Eleven Madison Avenue
                                                 New York, NY 10010-3629

     SIGNATURE PAGE TO THIRD AMENDED AND RESTATED SECURITYHOLDERS AGREEMENT

<PAGE>

                                        SECURITYHOLDERS:


                                        ----------------------------------------
                                        Eduardo Vazquez Arroyo Carstens
                                        Address:
                                                 -------------------------------


                                        ----------------------------------------
                                        Gabriel Agustin Vazquez Carstens
                                        Address:
                                                 -------------------------------


                                        ----------------------------------------
                                        Alina Georgina Carstens Martinez
                                        Address:
                                                 -------------------------------


                                        TELEREUNION INTERNATIONAL, S.A. DE C.V.


                                        By:
                                            ------------------------------------
                                        Name:
                                              ----------------------------------
                                        Its:
                                             -----------------------------------

                                        Address:
                                                 -------------------------------
                                        Telecopy:
                                                  ------------------------------
                                        Attention:
                                                   -----------------------------


                                        CONTROLADORA PROFESIONAL REGIOMONTANA,
                                        S.A. DE C.V.


                                        By:
                                            ------------------------------------
                                        Name:
                                              ----------------------------------
                                        Its:
                                             -----------------------------------

                                        Address:
                                                 -------------------------------
                                        Telecopy:
                                                  ------------------------------
                                        Attention:
                                                   -----------------------------

     SIGNATURE PAGE TO THIRD AMENDED AND RESTATED SECURITYHOLDERS AGREEMENT

<PAGE>


                                        ----------------------------------------
                                        Adrian Aguirre G.
                                        Address:
                                                 -------------------------------


                                        ----------------------------------------
                                        Maria Guadalupe Aguirre G.
                                        Address:
                                                 -------------------------------


                                        ----------------------------------------
                                        Maria Elena Aguirre G.
                                        Address:
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                                        ----------------------------------------
                                        Maria Trinidad Aguirre G.
                                        Address:
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                                        ----------------------------------------
                                        Ana Maria Aguirre G.
                                        Address:
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                                        ----------------------------------------
                                        Francisco Aguirre G.
                                        Address:
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                                        ----------------------------------------
                                        L. D. Coltrane, III
                                        Address:
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                                        ----------------------------------------
                                        Michael R. Coltrane
                                        Address:
                                                 -------------------------------

     SIGNATURE PAGE TO THIRD AMENDED AND RESTATED SECURITYHOLDERS AGREEMENT

<PAGE>


                                        ----------------------------------------
                                        Samuel E. Leftwich
                                        Address:
                                                 -------------------------------


                                        ----------------------------------------
                                        Thomas A. Norman
                                        Address:
                                                 -------------------------------


                                        AMSTERDAM PACIFIC LLC


                                        By:
                                            ------------------------------------
                                        Name:
                                              ----------------------------------
                                        Its:
                                             -----------------------------------

                                        Address:
                                                 -------------------------------
                                        Telecopy:
                                                  ------------------------------
                                        Attention:
                                                   -----------------------------


                                        ----------------------------------------
                                        German N. Carmona Garduno
                                        Address:
                                                 -------------------------------


                                        ----------------------------------------
                                        Miguel Lebrija Reygadas
                                        Address:
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                                        ----------------------------------------
                                        Klaus Bernd Meyer Hanft
                                        Address:
                                                 -------------------------------


                                        ----------------------------------------
                                        Benjamin Alvarez Manrique
                                        Address:
                                                 -------------------------------


                                        ----------------------------------------
                                        Laurence Carl Newell Garcia
                                        Address:
                                                 -------------------------------

     SIGNATURE PAGE TO THIRD AMENDED AND RESTATED SECURITYHOLDERS AGREEMENT

<PAGE>


                                        ----------------------------------------
                                        Roberto E. Newell Garcia
                                        Address:
                                                 -------------------------------


                                        ----------------------------------------
                                        Georges Armand Lafon
                                        Address:
                                                 -------------------------------


                                        ----------------------------------------
                                        Moises Goldberg Dryjansky
                                        Address:
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                                        ----------------------------------------
                                        David Weltz Sourasky
                                        Address:
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                                        ----------------------------------------
                                        Patricia Maria del Carmen Palme Sierra
                                        Address:
                                                 -------------------------------


                                        ----------------------------------------
                                        Edgardo Rivera Torres Suares
                                        Address:
                                                 -------------------------------


                                        ----------------------------------------
                                        Ral Guijarro de Pablo
                                        Address:
                                                 -------------------------------


                                        ----------------------------------------
                                        Gilberto Solis Silva
                                        Address:
                                                 -------------------------------


                                        ----------------------------------------
                                        Miguel Alfonso Sepulveda Martinez
                                        Address:
                                                 -------------------------------


                                        ----------------------------------------
                                        Rosa Maria Palme Sierra
                                        Address:
                                                 -------------------------------

     SIGNATURE PAGE TO THIRD AMENDED AND RESTATED SECURITYHOLDERS AGREEMENT
<PAGE>

                                   ATTACHMENTS

                                    EXHIBITS

Exhibit A: Company Bylaws

Exhibit B: Company Guidelines

<PAGE>

                                    EXHIBIT A

                                 Company Bylaws

                                 TO BE ATTACHED

<PAGE>

                                    EXHIBIT B

                               Company Guidelines

              MAXCOM TELECOMUNICACIONES, S.A. DE C.V., S.A. DE C.V.

Payment Practices:

     The United States Foreign Corrupt Practices Act (the "FCPA") prohibits,
among other things, certain payments and accounting practices and, if violated,
carries civil and criminal liability for Maxcom Telecomunicaciones, S.A. de C.V.
("Maxcom" or the "Company") and individual employees. In order to comply with
the FCPA, directors, employees, agents, contractors and affiliates, as
applicable, must observe the following rules:

     -    Business and Accounting Practices -- Company employees and agents
          shall adhere to all legal requirements of Mexico and each political
          subdivision thereof, and each other country in which the Company
          conducts business. The Company and all of its employees, agents,
          contractors and affiliates shall employ the highest ethical standards.
          No undisclosed or unrecorded Company fund or asset shall be
          established or utilized for any purpose, no false or misleading
          entries shall be made in the Company's books or records and all
          transactions of the Company shall be recorded on its books and
          records. No payment on the Company's behalf shall be without complete
          and proper supporting documentation or made for any purpose other than
          as described in such documentation and all payments will be made for
          lawful purposes only. Company personnel shall comply with generally
          accepted accounting rules, the FCPA and Company internal control
          policies at all times.

     -    Questionable Payments -- With the exception of certain regulatory fees
          set by the government and facilitating payments (defined below), all
          payments, promises to pay, offers of payment of anything of value to
          any official, foreign or otherwise, political party or official
          thereof from either the Company or private funds in furtherance of
          Company business are strictly prohibited. Where, in accordance with
          the practice and custom of a particular locale, the payment of a
          nominal sum (a "facilitating payment") must be made in order to induce
          an official of a foreign government to perform an act which the
          official would be required to perform in any event, such facilitating
          payment is not prohibited to the extent it is permitted under
          applicable law. These facilitating payments must be properly approved,
          documented and recorded on the Company's books.

     -    Political Contributions -- The Company, as a corporate entity, will
          not make any contributions or payments to political parties,
          candidates, or initiative or referendum campaigns, unless such
          payments are clearly permitted by law and approved by the appropriate
          Company officer. This restriction is not intended to discourage
          employees from making contributions to, or being involved with
          candidates, parties, initiative or referenda or political committees
          of their choice as private individuals. Such involvement, however,
          must be on the employees' own time and at their own expense and must
          in no way indicate the Company endorsement of or position relating to
          such activity.


                                       B-1

<PAGE>

Integrity of the Company Assets and Information:

     -    Trade Secrets -- Company assets are more than physical plants and
          equipment. They include technology and concepts, valuable ideas,
          business and product plans, as well as information about the business.
          All employees shall regard and preserve as confidential and shall not
          divulge to unauthorized persons any information of a secret,
          confidential, or private nature connected with the business of the
          Company or any of its suppliers, customers or affiliates without the
          prior written consent of the appropriate Company officer. No employee
          shall disclose to the Company or use to benefit the Company any
          confidential information which was obtained outside the Company,
          except as permitted by the terms of an applicable nondisclosure
          agreement.

     -    Accurate Reporting -- All employee reports of any kind (such as
          expense reports, hours worked, sales reports, etc.) must be completed
          accurately and honestly. Failure to so report, in addition to being a
          violation of Company policy, may also be illegal.

     -    Public Disclosure -- Since both the Company and individual employees
          may become liable to investors who buy or sell the Company stock in
          reliance on misleading or incomplete Company statements, all public
          statements must be accurate, and any projections of future performance
          must come from top level management. All inquiries from investors,
          securities or financial analysts or brokers involving requests for
          specific or detailed Company information should be directed to the
          appropriate Company officer.

     -    Employee Information -- The Company collects, uses and maintains only
          employee information that is required for business or legal reasons.
          The Company provides employees access to their personnel files as a
          means of insuring that information in such records is correct. The
          Company will not release employee information without the approval of
          the employee affected except to verify employment or to satisfy
          legitimate investigatory or legal requirements.

Conflict of Interest Policy:

     A conflict of interest is any activity or interest which is inconsistent
with, or opposed to the best interests of, the Company. Potential conflicts of
interest may arise in the following situations:

     -    Interest in Other Businesses -- Employees should not have any direct
          or indirect financial interest with a present customer, competitor or
          supplier that could cause divided loyalty or the appearance of divided
          loyalty. (This prohibition does not include passive investments of not
          more than three percent of the total outstanding shares of any company
          listed on a recognized Mexican, United States or other foreign or
          domestic stock exchange).

     -    Moonlighting -- The Company expects each employee (other than
          part-time employees) to devote his or her full time and attention to
          his or her commitment to the Company. Therefore, all such employees
          are discouraged from maintaining outside employment. Salaried
          employees may not engage in outside work or services for a current or
          potential: (i) customer, (ii) competitor or (iii) supplier of the
          Company under any circumstances. Salaried employees may engage in
          other outside business activities only with the prior written approval
          of the appropriate Company officer. Hourly employees may not engage in
          outside employment where such employment may create a conflict of
          interest (for example, working for a current or potential


                                       B-2

<PAGE>

          competitor). Hourly employees may engage in other outside business
          activities with the prior written approval of the appropriate Company
          officer. Under no circumstances may outside employment by any employee
          (other than part-time employees) lessen his or her efficiency,
          alertness, interest or productivity.

     -    Gifts and Other Gratuities -- No employee or any member of his or her
          household shall accept gifts or gratuities or other favored treatment
          from any person associated with a present or prospective customer or
          supplier of the Company. Similarly, no employee may give money or
          gifts to a customer, competitor or supplier if it could be reasonably
          viewed as being done to gain an unfair business advantage.

     -    Family -- No employee may conduct Company business with a person with
          whom he or she is related by blood, law or marriage, or a business
          organization with which the employee or person with whom such employee
          is related by blood, law or marriage has a significant association,
          without first having the prior written approval of the appropriate
          Company officer.

Trade Regulations:

     Trade laws and regulations in the United States and elsewhere are designed
to foster a competitive marketplace and prohibit activities in restraint of
trade. Generally any actions taken either individually, or in combination with
others, which are predatory toward a competitor or by nature restrain
competition, are most likely violations of one or more antitrust laws. The
following prohibitions, although not inclusive, represent significant practices
which are contrary to the policies of the Company and are prohibited.

     -    Arrangements or understandings with competitors or potential
          competitors concerning prices of products or other competitive
          policies or practices are strictly prohibited and shall not be even
          the subject of discussion by any Company employee with a competitor or
          potential competitor.

     -    In any potential or actual joint venture or projects with competitors
          or potential competitors, all discussions must be limited to the
          specific transactions involved.

     -    Participation in trade associations, seminars or other groups must not
          be, or even appear to be, an occasion for any discussion of
          competitive policies and practices.

     -    Arrangements or understandings with a particular competitor or
          customer, potential competitor or potential customer not to deal with
          a particular customer or supplier or potential customer or potential
          supplier are strictly prohibited.

     -    Agreements or understandings whereby Company customers or potential
          customers agree with the Company not to purchase the goods or services
          of a competitor or a potential competitor of the Company are strictly
          prohibited.

Environmental Policy:

     -    Basic Policy - It is the policy of the Company to conduct its
          activities with due


                                       B-3

<PAGE>

          concern for the human and natural environment while making and
          marketing safe and high quality products and services for its
          customers. This is to be accomplished in a manner that will benefit
          the present and future well-being of the communities in which the
          Company maintains or plans to maintain facilities and conducts
          business activities. The Company and its affiliates, agents and
          employees shall, at all times, operate as good corporate citizens and
          meet or exceed all applicable environmental laws and regulations.

     -    Responsibility - The Chief Operating Officer shall be responsible for
          conducting the Company's operations in a manner that assures
          compliance with environmental laws and with the Company's policy. Each
          facility shall maintain an environmental management and compliance
          program appropriate to its operations in fulfillment of this
          responsibility. Environmental factors shall be taken into
          consideration in the development of all business plans, operations and
          activities.

     -    The Director of External Affairs is responsible for providing program
          management direction, establishing program guidelines, advising
          personnel of regulatory requirements and assisting in meeting
          compliance responsibilities.

     -    Reports - The following environmental regulatory events shall be
          promptly communicated to the Director of External Affairs and the
          Chief Operating Officer: (1) regulatory agency permit notices; (2)
          reports on test results, internal or agency, indicating permit
          noncompliance; (3) notices of noncompliance with environmental
          regulations or permits; (4) negotiations or orders involving
          regulation or permit compliance; and (5) environmental related
          incidents which are reportable to any governmental agency or could
          result in a negative impact on the Company.

Employment Discrimination and Harassment:

     The Company maintains a policy of nondiscrimination towards employees and
applicants for employment. No aspect of hiring or employment will be influenced
in any manner by race, color, religion, sex, age, national origin, disability,
or any other basis prohibited by statute.

     The Company also strives to afford all employees a workplace free from
sexual harassment. The Company prohibits unwelcome sexual advances, requests for
sexual favors, and other verbal or physical conduct of a sexual nature (whether
implicit or explicit) where such conduct has the purpose or effect of
unreasonably interfering with an individual's work performance or creating an
intimidating, hostile or offensive work environment. The Company also prohibits
harassment not overtly sexual in nature but directed at, or commenting on,
attributes or characteristics of a person solely because of, or on the basis of,
his or her sex. Finally, the Company prohibits retaliation against any person
who refuses or objects to unwelcome verbal or physical conduct or who reports
any of the above conduct.

     All supervisory and management personnel are responsible for assuring a
workplace free from discrimination and harassment. All employees are responsible
for refraining from all forms of discriminatory or harassing conduct or
language.

Procurement Policy:


                                       B-4

<PAGE>

     Procurement decisions are to be made only with the participation of the
Company's purchasing, legal and accounting departments and in accordance with
the procurement policies of the Company. Exceptions to this policy may be made
only with the approval of the appropriate Company officer.

Compliance:

     Admittedly no summary of guidelines for ethical business conduct covers
every instance. The absence of a guideline covering a particular situation does
not relieve the employee from the responsibility to operate with the highest
ethical standards of business conduct. Because each Company employee, in the
final analysis, is responsible for his or her actions, no Company employee
should hesitate to seek guidance and assistance for any questions regarding
compliance. The responsibility for administering these standards is delegated to
the appropriate Company officer with respect to the employees within their
jurisdiction. In addition, each employee has the responsibility to report
unethical business practices or violations of the Company's Standards of
Business Conduct to the officer or director in charge of internal controls who
will investigate such violations and report serious violations to the Company's
board of directors.

     Each of the Chief Operating Officer, the Chief Executive Officer and the
President is charged with bringing matters concerning his own conduct to the
Board.

     Each employee's ultimate responsibility is to the Company, not to any
individual, and to comply with the law. If an employee believes his or her
superior is not responding to a clear violation of these policies or the law, it
is that employee's duty, however unpleasant, to inform the next superior
officer, and if the matter is not addressed, ultimately the Chief Executive
Officer and the Board. Each employee shall also have the right to bring any such
matters to the attention of the Board.

     Integrity is a matter of character. Each Company employee must insist that
each other Company employee, individually, and collectively, always meet the
highest ethical standards of business conduct.

Disciplinary Actions:

     Maxcom will take appropriate disciplinary action against employees that
violate these guidelines, which disciplinary action will be consistent with
applicable law.

                                     ******


                                      B-5